spark.locality.wait set to 100000 in examples/graphx/Analytics.scala.
Should be left to the user.

Author: Ernest <earneyzxl@gmail.com>

Closes #3730 from Earne/SPARK-4880 and squashes the following commits:

d79ed04 [Ernest] remove spark.locality.wait in Analytics

The original test doesn't make sense since if you step in, the lossSum is already NaN,
and the coefficients are diverging. That's because the step size is too large for SGD,
so it doesn't work.

The correct behavior is that you should get smaller coefficients than the one
without regularization. Comparing the values using 20000.0 relative error doesn't
make sense as well.

Author: DB Tsai <dbtsai@alpinenow.com>

Closes #3735 from dbtsai/mlortestfix and squashes the following commits:

b1a3c42 [DB Tsai] first commit

Hi all - cleaned up the code to get rid of the unused parameter and added some discussion of the ThreadPoolExecutor parameters to explain why we can use a single threadCount instead of providing a min/max.

Author: Ilya Ganelin <ilya.ganelin@capitalone.com>

Closes #3664 from ilganeli/SPARK-3607C and squashes the following commits:

3c05690 [Ilya Ganelin] Updated documentation and refactored code to extract shared variables

Author: Timothy Chen <tnachen@gmail.com>

Closes #3349 from tnachen/mesos_doc and squashes the following commits:

737ef49 [Timothy Chen] Add TOC
5ca546a [Timothy Chen] Update description around cores requested.
26283a5 [Timothy Chen] Add mesos specific configurations into doc

... changed to a time period

Author: Sandy Ryza <sandy@cloudera.com>

Closes #3471 from sryza/sandy-spark-3779 and squashes the following commits:

20b9887 [Sandy Ryza] Deprecate old property
42b5df7 [Sandy Ryza] Review feedback
9a959a1 [Sandy Ryza] SPARK-3779. yarn spark.yarn.applicationMaster.waitTries config should be changed to a time period

Currently, there is no way to pass yarn am specific java options. It cause some potential issues when reading classpath from hadoop configuration file. Hadoop configuration actually replace variables in its property with the system property passed in java options. How to specify the value depends on different hadoop distribution.

The new options are SPARK_YARN_JAVA_OPTS or spark.yarn.extraJavaOptions. I make it as spark global level, because typically we don't want user to specify this in their command line each time submitting spark job after it is setup in spark-defaults.conf.

In addition, with this new extra options enabled to be passed to AM, it provides more flexibility.

For example int the following valid mapred-site.xml file, we have the class path which specify values using system property. Hadoop can correctly handle it because it has java options passed in.

This is the example, currently spark will break due to hadoop.version is not passed in.
  <property>
    <name>mapreduce.application.classpath</name>
    <value>/etc/hadoop/${hadoop.version}/mapreduce/*</value>
  </property>

In the meantime, we cannot relies on  mapreduce.admin.map.child.java.opts in mapred-site.xml, because it has its own extra java options specified, which does not apply to Spark.

Author: Zhan Zhang <zhazhan@gmail.com>

Closes #3409 from zhzhan/Spark-4461 and squashes the following commits:

daec3d0 [Zhan Zhang] solve review comments
08f44a7 [Zhan Zhang] add warning in driver mode if spark.yarn.am.extraJavaOptions is configured
5a505d3 [Zhan Zhang] solve review comments
4ed43ad [Zhan Zhang] solve review comments
ad777ed [Zhan Zhang] Merge branch 'master' into Spark-4461
3e9e574 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
e3f9abe [Zhan Zhang] solve review comments
8963552 [Zhan Zhang] rebase
f8f6700 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
dea1692 [Zhan Zhang] change the option key name to client mode specific
90d5dff [Zhan Zhang] rebase
8ac9254 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
092a25f [Zhan Zhang] solve review comments
bc5a9ae [Zhan Zhang] solve review comments
782b014 [Zhan Zhang] add new configuration to docs/running-on-yarn.md and remove it from spark-defaults.conf.template
6faaa97 [Zhan Zhang] solve review comments
369863f [Zhan Zhang] clean up unnecessary var
733de9c [Zhan Zhang] Merge branch 'master' into Spark-4461
a68e7f0 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
864505a [Zhan Zhang] Add extra java options to be passed to Yarn application master
15830fc [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
685d911 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
03ebad3 [Zhan Zhang] Merge branch 'master' of https://github.com/zhzhan/spark
46d9e3d [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
ebb213a [Zhan Zhang] revert
b983ef3 [Zhan Zhang] test
c4efb9b [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
779d67b [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
4daae6d [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
12e1be5 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
ce0ca7b [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
93f3081 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
3764505 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
a9d372b [Zhan Zhang] Merge branch 'master' of https://github.com/zhzhan/spark
a00f60f [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
497b0f4 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
4a2e36d [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
a72c0d4 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
301eb4a [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
cedcc6f [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
adf4924 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
d10bf00 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
7e0cc36 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
68deb11 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
3ee3b2b [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
2b0d513 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
1ccd7cc [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
af9feb9 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
e4c1982 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
921e914 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
789ea21 [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
cb53a2c [Zhan Zhang] Merge branch 'master' of https://github.com/apache/spark
f6a8a40 [Zhan Zhang] revert
ba14f28 [Zhan Zhang] test

Modify python annotations for sphinx. There is no change to build process from.
https://github.com/apache/spark/blob/master/docs/README.md

Author: lewuathe <lewuathe@me.com>

Closes #3685 from Lewuathe/sphinx-tag-for-pydoc and squashes the following commits:

88a0fd9 [lewuathe] [SPARK-4822] Fix DevelopApi and WARN tags
3d7a398 [lewuathe] [SPARK-4822] Use sphinx tags for Python doc annotations

This commit exists to close the following pull requests on Github:

Closes #3137 (close requested by 'marmbrus')
Closes #3362 (close requested by 'marmbrus')
Closes #2979 (close requested by 'JoshRosen')
Closes #2223 (close requested by 'JoshRosen')
Closes #2998 (close requested by 'marmbrus')
Closes #3202 (close requested by 'marmbrus')
Closes #3079 (close requested by 'marmbrus')
Closes #3210 (close requested by 'marmbrus')
Closes #2764 (close requested by 'marmbrus')
Closes #3618 (close requested by 'marmbrus')
Closes #3501 (close requested by 'marmbrus')
Closes #2768 (close requested by 'marmbrus')
Closes #3381 (close requested by 'marmbrus')
Closes #3510 (close requested by 'marmbrus')
Closes #3703 (close requested by 'marmbrus')
Closes #2543 (close requested by 'marmbrus')
Closes #2876 (close requested by 'marmbrus')
Closes #1281 (close requested by 'JoshRosen')

[SPARK-3891][SQL] Add array support to percentile, percentile_approx and constant inspectors support

Supported passing array to percentile and percentile_approx UDAFs
To support percentile_approx,  constant inspectors are supported for GenericUDAF
Constant folding support added to CreateArray expression
Avoided constant udf expression re-evaluation

Author: Venkata Ramana G <ramana.gollamudihuawei.com>

Author: Venkata Ramana Gollamudi <ramana.gollamudi@huawei.com>

Closes #2802 from gvramana/percentile_array_support and squashes the following commits:

a0182e5 [Venkata Ramana Gollamudi] fixed review comment
a18f917 [Venkata Ramana Gollamudi] avoid constant udf expression re-evaluation - fixes failure due to return iterator and value type mismatch
c46db0f [Venkata Ramana Gollamudi] Removed TestHive reset
4d39105 [Venkata Ramana Gollamudi] Unified inspector creation, style check fixes
f37fd69 [Venkata Ramana Gollamudi] Fixed review comments
47f6365 [Venkata Ramana Gollamudi] fixed test
cb7c61e [Venkata Ramana Gollamudi] Supported ConstantInspector for UDAF Fixed HiveUdaf wrap object issue.
7f94aff [Venkata Ramana Gollamudi] Added foldable support to CreateArray

```
TestSQLContext.sparkContext.parallelize(
  """{"ip":"27.31.100.29","headers":{"Host":"1.abc.com","Charset":"UTF-8"}}""" ::
  """{"ip":"27.31.100.29","headers":{}}""" ::
  """{"ip":"27.31.100.29","headers":""}""" :: Nil)
```
As empty string (the "headers") will be considered as String in the beginning (in line 2 and 3), it ignores the real nested data type (struct type "headers" in line 1), and also take the line 1 (the "headers") as String Type, which is not our expected.

Author: Cheng Hao <hao.cheng@intel.com>

Closes #3708 from chenghao-intel/json and squashes the following commits:

e7a72e9 [Cheng Hao] add more concise unit test
853de51 [Cheng Hao] NullType instead of StringType when sampling against empty string or null value

Author: Michael Armbrust <michael@databricks.com>

Closes #3727 from marmbrus/parquetNotEq and squashes the following commits:

2157bfc [Michael Armbrust] Fix parquet filter suite

+ small doc edit
+ include edit to make IntelliJ happy

CC: davies  mengxr

Note to davies  -- this does not fix the "WARNING: Literal block expected; none found." warnings since that seems to involve spacing which IntelliJ does not like.  (Those warnings occur when generating the Python docs.)

Author: Joseph K. Bradley <joseph@databricks.com>

Closes #3669 from jkbradley/python-warnings and squashes the following commits:

4587868 [Joseph K. Bradley] fixed warning
8cb073c [Joseph K. Bradley] Updated based on davies recommendation
c51eca4 [Joseph K. Bradley] Updated rst file for pyspark.mllib.rand doc.  Small doc edit.  Small include edit to make IntelliJ happy.

In local mode, Hadoop/Hive will ignore the "mapred.map.tasks", hence for small table file, it's always a single input split, however, SparkSQL doesn't honor that in table scanning, and we will get different result when do the Hive Compatibility test. This PR will fix that.

Author: Cheng Hao <hao.cheng@intel.com>

Closes #2589 from chenghao-intel/source_split and squashes the following commits:

dff38e7 [Cheng Hao] Remove the extra blank line
160a2b6 [Cheng Hao] fix the compiling bug
04d67f7 [Cheng Hao] Keep 1 split for small file in table scanning

Author: Daoyuan Wang <daoyuan.wang@intel.com>

Closes #3616 from adrian-wang/sqrt and squashes the following commits:

d877439 [Daoyuan Wang] fix NULLTYPE
3effa2c [Daoyuan Wang] sqrt(negative value) should return null

Predicates like `a = NULL` and `a < NULL` can't be pushed down since Parquet `Lt`, `LtEq`, `Gt`, `GtEq` doesn't accept null value. Note that `Eq` and `NotEq` can only be used with `null` to represent predicates like `a IS NULL` and `a IS NOT NULL`.

However, normally this issue doesn't cause NPE because any value compared to `NULL` results `NULL`, and Spark SQL automatically optimizes out `NULL` predicate in the `SimplifyFilters` rule. Only testing code that intentionally disables the optimizer may trigger this issue. (That's why this issue is not marked as blocker and I do **NOT** think we need to backport this to branch-1.1

This PR restricts `Lt`, `LtEq`, `Gt` and `GtEq` to non-null values only, and only uses `Eq` with null value to pushdown `IsNull` and `IsNotNull`. Also, added support for Parquet `NotEq` filter for completeness and (tiny) performance gain, it's also used to pushdown `IsNotNull`.

<!-- Reviewable:start -->
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Author: Cheng Lian <lian@databricks.com>

Closes #3367 from liancheng/filters-with-null and squashes the following commits:

cc41281 [Cheng Lian] Fixes several styling issues
de7de28 [Cheng Lian] Adds stricter rules for Parquet filters with null

Based on #2543.

Author: Michael Armbrust <michael@databricks.com>

Closes #3724 from marmbrus/resolveGetField and squashes the following commits:

0a47aae [Michael Armbrust] Fix case insensitive resolution of GetField.

HiveThriftServer2 can not exit automactic when changing the standy resource manager in Yarn HA mode.
The scheduler backend was aware of the AM had been exited so it call sc.stop to exit the driver process but there was a user thread(HiveThriftServer2 ) which was still alive and cause this problem.
To fix it, make a demo thread to detect the sparkContext is null or not.If the sc is stopped, call the ThriftServer.stop to stop the user thread.

Author: carlmartin <carlmartinmax@gmail.com>

Closes #3576 from SaintBacchus/ThriftServer2ExitBug and squashes the following commits:

2890b4a [carlmartin] Use SparkListener instead of the demo thread to stop the hive server.
c15da0e [carlmartin] HiveThriftServer2 can not exit automactic when changing the standy resource manager in Yarn HA mode

Add `sort by` support for both DSL & SqlParser.

This PR is relevant with #3386, either one merged, will cause the other rebased.

Author: Cheng Hao <hao.cheng@intel.com>

Closes #3481 from chenghao-intel/sortby and squashes the following commits:

041004f [Cheng Hao] Add sort by for DSL & SimpleSqlParser

`MetricsServlet` handler should be added to the web UI after initialized by `MetricsSystem`, otherwise servlet handler cannot be attached.

Author: Saisai Shao <saisai.shao@intel.com>
Author: Josh Rosen <joshrosen@databricks.com>
Author: jerryshao <saisai.shao@intel.com>

Closes #3444 from jerryshao/SPARK-4595 and squashes the following commits:

434d17e [Saisai Shao] Merge pull request #10 from JoshRosen/metrics-system-cleanup
87a2292 [Josh Rosen] Guard against misuse of MetricsSystem methods.
f779fe0 [jerryshao] Fix MetricsServlet not work issue

Author: Josh Rosen <joshrosen@databricks.com>

Closes #3719 from JoshRosen/rat-fix and squashes the following commits:

1542886 [Josh Rosen] [HOTFIX] Fix RAT exclusion for known_translations file

Additionally, we now warn the user when a duplicate author name
arises, in which case he/she needs to resolve it manually.

Using lowercase for ```options``` key to make it case-insensitive, then we should use lower case to get value from parameters.
So flowing cmd work
```
      create temporary table normal_parquet
      USING org.apache.spark.sql.parquet
      OPTIONS (
        PATH '/xxx/data'
      )
```

Author: scwf <wangfei1@huawei.com>
Author: wangfei <wangfei1@huawei.com>

Closes #3470 from scwf/ddl-ulcase and squashes the following commits:

ae78509 [scwf] address comments
8f4f585 [wangfei] address comments
3c132ef [scwf] minor fix
a0fc20b [scwf] Merge branch 'master' of https://github.com/apache/spark into ddl-ulcase
4f86401 [scwf] adding CaseInsensitiveMap
e244e8d [wangfei] using lower case in json
e0cb017 [wangfei] make options in-casesensitive

This PR brings support of using StructType(and other hashable types) as key in MapType.

Author: Davies Liu <davies@databricks.com>

Closes #3714 from davies/fix_struct_in_map and squashes the following commits:

68585d7 [Davies Liu] fix primitive types in MapType
9601534 [Davies Liu] support StructType as key in MapType

Author: Cheng Hao <hao.cheng@intel.com>

Closes #3595 from chenghao-intel/udf0 and squashes the following commits:

a858973 [Cheng Hao] Add 0 arguments support for udf

This is a follow-up of SPARK-4593 (#3443).

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #3581 from ueshin/issues/SPARK-4720 and squashes the following commits:

c3959d4 [Takuya UESHIN] Make Remainder return null if the divider is 0.

Author: Cheng Hao <hao.cheng@intel.com>

Closes #3606 from chenghao-intel/codegen_short_circuit and squashes the following commits:

f466303 [Cheng Hao] short circuit for AND & OR

This PR provides a set Parquet testing API (see trait `ParquetTest`) that enables developers to write more concise test cases. A new set of Parquet test suites built upon this API  are added and aim to replace the old `ParquetQuerySuite`. To avoid potential merge conflicts, old testing code are not removed yet. The following classes can be safely removed after most Parquet related PRs are handled:

- `ParquetQuerySuite`
- `ParquetTestData`

<!-- Reviewable:start -->
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<!-- Reviewable:end -->

Author: Cheng Lian <lian@databricks.com>

Closes #3644 from liancheng/parquet-tests and squashes the following commits:

800e745 [Cheng Lian] Enforces ordering of test output
3bb8731 [Cheng Lian] Refactors HiveParquetSuite
aa2cb2e [Cheng Lian] Decouples ParquetTest and TestSQLContext
7b43a68 [Cheng Lian] Updates ParquetTest Scaladoc
7f07af0 [Cheng Lian] Adds a new set of Parquet test suites

This bypasses unnecessary calls to the Github and JIRA API.
Additionally, having a local cache allows us to remember names
that we had to manually discover ourselves.

This commit introduces several major improvements to the script
that generates the contributors list for release notes, notably:

(1) Use release tags instead of a range of commits. Across branches,
commits are not actually strictly two-dimensional, and so it is not
sufficient to specify a start hash and an end hash. Otherwise, we
end up counting commits that were already merged in an older branch.

(2) Match PR numbers in addition to commit hashes. This is related
to the first point in that if a PR is already merged in an older
minor release tag, it should be filtered out here. This requires us
to do some intelligent regex parsing on the commit description in
addition to just relying on the GitHub API.

(3) Relax author validity check. The old code fails on a name that
has many middle names, for instance. The test was just too strict.

(4) Use GitHub authentication. This allows us to make far more
requests through the GitHub API than before (5000 as opposed to 60
per hour).

(5) Translate from Github username, not commit author name. This is
important because the commit author name is not always configured
correctly by the user. For instance, the username "falaki" used to
resolve to just "Hossein", which was treated as a github username
and translated to something else that is completely arbitrary.

(6) Add an option to use the untranslated name. If there is not
a satisfactory candidate to replace the untranslated name with,
at least allow the user to not translate it.

In BroadcastHashJoin, currently it is using a hard coded value (5 minutes) to wait for the execution and broadcast of the small table.
In my opinion, it should be a configurable value since broadcast may exceed 5 minutes in some case, like in a busy/congested network environment.

Author: Jacky Li <jacky.likun@huawei.com>

Closes #3133 from jackylk/timeout-config and squashes the following commits:

733ac08 [Jacky Li] add spark.sql.broadcastTimeout in SQLConf.scala
557acd4 [Jacky Li] switch to sqlContext.getConf
81a5e20 [Jacky Li] make wait time configurable in BroadcastHashJoin

Since `AttributeReference` resolution and `*` expansion are currently in separate rules, each pair requires a full iteration instead of being able to resolve in a single pass.  Since its pretty easy to construct queries that have many of these in a row, I combine them into a single rule in this PR.

Author: Michael Armbrust <michael@databricks.com>

Closes #3674 from marmbrus/projectStars and squashes the following commits:

d83d6a1 [Michael Armbrust] Fix resolution of deeply nested Project(attr, Project(Star,...)).

In `HashOuterJoin.scala`, spark read data from both side of join operation before zip them together. It is a waste for memory. We are trying to read data from only one side, put them into a hashmap, and then generate the `JoinedRow` with data from other side one by one.
Currently, we could only do this optimization for `left outer join` and `right outer join`. For `full outer join`, we will do something in another issue.

for
table test_csv contains 1 million records
table dim_csv contains 10 thousand records

SQL:
`select * from test_csv a left outer join dim_csv b on a.key = b.key`

the result is:
master:
```
CSV: 12671 ms
CSV: 9021 ms
CSV: 9200 ms
Current Mem Usage:787788984
```
after patch：
```
CSV: 10382 ms
CSV: 7543 ms
CSV: 7469 ms
Current Mem Usage:208145728
```

Author: tianyi <tianyi@asiainfo-linkage.com>
Author: tianyi <tianyi.asiainfo@gmail.com>

Closes #3375 from tianyi/SPARK-4483 and squashes the following commits:

72a8aec [tianyi] avoid having mutable state stored inside of the task
99c5c97 [tianyi] performance optimization
d2f94d7 [tianyi] fix bug: missing output when the join-key is null.
2be45d1 [tianyi] fix spell bug
1f2c6f1 [tianyi] remove commented codes
a676de6 [tianyi] optimize some codes
9e7d5b5 [tianyi] remove commented old codes
838707d [tianyi] Optimization about reduce memory costs during the HashOuterJoin

In `JoinSuite` add BroadcastNestedLoopJoin operator selection testsuite

Author: wangxiaojing <u9jing@gmail.com>

Closes #3395 from wangxiaojing/SPARK-4527 and squashes the following commits:

ea0e495 [wangxiaojing] change style
53c3952 [wangxiaojing] Add BroadcastNestedLoopJoin operator selection testsuite

Placement groups are cool and all the cool kids are using them. Lets add support for them to spark_ec2.py because I'm lazy

Author: Holden Karau <holden@pigscanfly.ca>

Closes #3623 from holdenk/SPARK-4767-add-support-for-launching-in-a-specified-placement-group-to-spark-ec2-scripts and squashes the following commits:

111a5fd [Holden Karau] merge in master
70ace25 [Holden Karau] Placement groups are cool and all the cool kids are using them. Lets add support for them to spark_ec2.py because I'm lazy

The problem is `codegenEnabled` is `val`, but it uses a `val` `sqlContext`, which can be override by subclasses. Here is a simple example to show this issue.

```Scala
scala> :paste
// Entering paste mode (ctrl-D to finish)

abstract class Foo {

  protected val sqlContext = "Foo"

  val codegenEnabled: Boolean = {
    println(sqlContext) // it will call subclass's `sqlContext` which has not yet been initialized.
    if (sqlContext != null) {
      true
    } else {
      false
    }
  }
}

class Bar extends Foo {
  override val sqlContext = "Bar"
}

println(new Bar().codegenEnabled)

// Exiting paste mode, now interpreting.

null
false
defined class Foo
defined class Bar
```

We should make `sqlContext` `final` to prevent subclasses from overriding it incorrectly.

Author: zsxwing <zsxwing@gmail.com>

Closes #3660 from zsxwing/SPARK-4812 and squashes the following commits:

1cbb623 [zsxwing] Make `sqlContext` final to prevent subclasses from overriding it incorrectly

Author: jerryshao <saisai.shao@intel.com>

Closes #3698 from jerryshao/SPARK-4847 and squashes the following commits:

4741130 [jerryshao] Make later added extraStrategies effect when calling strategies

* This commit hopes to avoid the confusion I faced when trying
  to submit a regular, valid multi-line JSON file, also see

  http://apache-spark-user-list.1001560.n3.nabble.com/Loading-JSON-Dataset-fails-with-com-fasterxml-jackson-databind-JsonMappingException-td20041.html

Author: Peter Vandenabeele <peter@vandenabeele.com>

Closes #3517 from petervandenabeele/pv-docs-note-on-jsonFile-format/01 and squashes the following commits:

1f98e52 [Peter Vandenabeele] Revert to people.json and simple Note text
6b6e062 [Peter Vandenabeele] Change the "JSON" connotation to "txt"
fca7dfb [Peter Vandenabeele] Add a Note on jsonFile having separate JSON objects per line

Add HTTP protocol support and test cases to spark thrift server, so users can deploy thrift server in both TCP and http mode.

Author: Judy Nash <judynash@microsoft.com>
Author: judynash <judynash@microsoft.com>

Closes #3672 from judynash/master and squashes the following commits:

526315d [Judy Nash] correct spacing on startThriftServer method
31a6520 [Judy Nash] fix code style issues and update sql programming guide format issue
47bf87e [Judy Nash] modify withJdbcStatement method definition to meet less than 100 line length
2e9c11c [Judy Nash] add thrift server in http mode documentation on sql programming guide
1cbd305 [Judy Nash] Merge remote-tracking branch 'upstream/master'
2b1d312 [Judy Nash] updated http thrift server support based on feedback
377532c [judynash] add HTTP protocol spark thrift server

Based on this gist:
https://gist.github.com/amar-analytx/0b62543621e1f246c0a2

We use security group ids instead of security group to get around this issue:
https://github.com/boto/boto/issues/350

Author: Mike Jennings <mvj101@gmail.com>
Author: Mike Jennings <mvj@google.com>

Closes #2872 from mvj101/SPARK-3405 and squashes the following commits:

be9cb43 [Mike Jennings] `pep8 spark_ec2.py` runs cleanly.
4dc6756 [Mike Jennings] Remove duplicate comment
731d94c [Mike Jennings] Update for code review.
ad90a36 [Mike Jennings] Merge branch 'master' of https://github.com/apache/spark into SPARK-3405
1ebffa1 [Mike Jennings] Merge branch 'master' into SPARK-3405
52aaeec [Mike Jennings] [SPARK-3405] add subnet-id and vpc-id options to spark_ec2.py

This PR tests the pyspark Chi-squared hypothesis test from this commit: c8abddc5 and moves some of the error messaging in to python.

It is a port of the Scala tests here: [HypothesisTestSuite.scala](https://github.com/apache/spark/blob/master/mllib/src/test/scala/org/apache/spark/mllib/stat/HypothesisTestSuite.scala)

Hopefully, SPARK-2980 can be closed.

Author: jbencook <jbenjamincook@gmail.com>

Closes #3679 from jbencook/master and squashes the following commits:

44078e0 [jbencook] checking that bad input throws the correct exceptions
f12ee10 [jbencook] removing checks for ValueError since input tests are on the Scala side
7536cf1 [jbencook] removing python checks for invalid input
a17ee84 [jbencook] [SPARK-2980][mllib] adding unit tests for the pyspark chi-squared test
3aeb0d9 [jbencook] [SPARK-2980][mllib] bringing Chi-squared error messages to the python side