[SPARK-16535][BUILD] In pom.xml, remove groupId which is redundant definition and inherited from the parent

https://issues.apache.org/jira/browse/SPARK-16535

## What changes were proposed in this pull request?

When I scan through the pom.xml of sub projects, I found this warning as below and attached screenshot
```
Definition of groupId is redundant, because it's inherited from the parent
```
![screen shot 2016-07-13 at 3 13 11 pm](https://cloud.githubusercontent.com/assets/3925641/16823121/744f893e-4916-11e6-8a52-042f83b9db4e.png)

I've tried to remove some of the lines with groupId definition, and the build on my local machine is still ok.
```
<groupId>org.apache.spark</groupId>
```
As I just find now `<maven.version>3.3.9</maven.version>` is being used in Spark 2.x, and Maven-3 supports versionless parent elements: Maven 3 will remove the need to specify the parent version in sub modules. THIS is great (in Maven 3.1).

ref: http://stackoverflow.com/questions/3157240/maven-3-worth-it/3166762#3166762

## How was this patch tested?

I've tested by re-building the project, and build succeeded.

Author: Xin Ren <iamshrek@126.com>

Closes #14189 from keypointt/SPARK-16535.

## What changes were proposed in this pull request?
After SPARK-16476 (committed earlier today as #14128), we can finally bump the version number.

## How was this patch tested?
N/A

Author: Reynold Xin <rxin@databricks.com>

Closes #14130 from rxin/SPARK-16477.

## What changes were proposed in this pull request?

This PR moves flume back to Spark as per the discussion in the dev mail-list.

## How was this patch tested?

Existing Jenkins tests.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #11895 from zsxwing/move-flume-back.

[SPARK-13843][STREAMING] Remove streaming-flume, streaming-mqtt, streaming-zeromq, streaming-akka, streaming-twitter to Spark packages

## What changes were proposed in this pull request?

Currently there are a few sub-projects, each for integrating with different external sources for Streaming.  Now that we have better ability to include external libraries (spark packages) and with Spark 2.0 coming up, we can move the following projects out of Spark to https://github.com/spark-packages

- streaming-flume
- streaming-akka
- streaming-mqtt
- streaming-zeromq
- streaming-twitter

They are just some ancillary packages and considering the overhead of maintenance, running tests and PR failures, it's better to maintain them out of Spark. In addition, these projects can have their different release cycles and we can release them faster.

I have already copied these projects to https://github.com/spark-packages

## How was this patch tested?

Jenkins tests

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #11672 from zsxwing/remove-external-pkg.

This patch changes Spark's build to make Scala 2.11 the default Scala version. To be clear, this does not mean that Spark will stop supporting Scala 2.10: users will still be able to compile Spark for Scala 2.10 by following the instructions on the "Building Spark" page; however, it does mean that Scala 2.11 will be the default Scala version used by our CI builds (including pull request builds).

The Scala 2.11 compiler is faster than 2.10, so I think we'll be able to look forward to a slight speedup in our CI builds (it looks like it's about 2X faster for the Maven compile-only builds, for instance).

After this patch is merged, I'll update Jenkins to add new compile-only jobs to ensure that Scala 2.10 compilation doesn't break.

Author: Josh Rosen <joshrosen@databricks.com>

Closes #10608 from JoshRosen/SPARK-6363.

Author: Reynold Xin <rxin@databricks.com>

Closes #10387 from rxin/version-bump.

Author: Reynold Xin <rxin@databricks.com>

Closes #8350 from rxin/1.6.

This PR removed the `outputFile` configuration from pom.xml and updated `tests.py` to search jars for both sbt build and maven build.

I ran ` mvn -Pkinesis-asl -DskipTests clean install` locally, and verified the jars in my local repository were correct. I also checked Python tests for maven build, and it passed all tests.

Author: zsxwing <zsxwing@gmail.com>

Closes #8373 from zsxwing/SPARK-10168 and squashes the following commits:

e0b5818 [zsxwing] Fix the sbt build
c697627 [zsxwing] Add the jar pathes to the exception message
be1d8a5 [zsxwing] Fix the issue that maven publishes wrong artifact jars

Removed contents already included in Spark assembly jar from spark-streaming-XXX-assembly jars.

Author: zsxwing <zsxwing@gmail.com>

Closes #8069 from zsxwing/SPARK-9574.

Also, add support for the *-provided profiles. This avoids repackaging
things that are already in the Spark assembly, or, in the case of the
*-provided profiles, are provided by the distribution.

The flume-ng-auth dependency was also excluded since it's not really
used by Spark.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #7247 from vanzin/SPARK-8852 and squashes the following commits:

298a7d5 [Marcelo Vanzin] Feedback.
c962082 [Marcelo Vanzin] [SPARK-8852] [flume] Trim dependencies in flume assembly.

Author: zsxwing <zsxwing@gmail.com>

Closes #6830 from zsxwing/flume-python and squashes the following commits:

78dfdac [zsxwing] Fix the compile error in the test code
f1bf3c0 [zsxwing] Address TD's comments
0449723 [zsxwing] Add sbt goal streaming-flume-assembly/assembly
e93736b [zsxwing] Fix the test case for determine_modules_to_test
9d5821e [zsxwing] Fix pyspark_core dependencies
f9ee681 [zsxwing] Merge branch 'master' into flume-python
7a55837 [zsxwing] Add streaming_flume_assembly to run-tests.py
b96b0de [zsxwing] Merge branch 'master' into flume-python
ce85e83 [zsxwing] Fix incompatible issues for Python 3
01cbb3d [zsxwing] Add import sys
152364c [zsxwing] Fix the issue that StringIO doesn't work in Python 3
14ba0ff [zsxwing] Add flume-assembly for sbt building
b8d5551 [zsxwing] Merge branch 'master' into flume-python
4762c34 [zsxwing] Fix the doc
0336579 [zsxwing] Refactor Flume unit tests and also add tests for Python API
9f33873 [zsxwing] Add the Python API for Flume

Author: Patrick Wendell <patrick@databricks.com>

Closes #6328 from pwendell/spark-1.5-update and squashes the following commits:

2f42d02 [Patrick Wendell] A few more excludes
4bebcf0 [Patrick Wendell] Update to RC4
61aaf46 [Patrick Wendell] Using new release candidate
55f1610 [Patrick Wendell] Another exclude
04b4f04 [Patrick Wendell] More issues with transient 1.4 changes
36f549b [Patrick Wendell] [SPARK-7801] [BUILD] Updating versions to SPARK 1.5.0

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #5056 from vanzin/SPARK-6371 and squashes the following commits:

63220df [Marcelo Vanzin] Merge branch 'master' into SPARK-6371
6506f75 [Marcelo Vanzin] Use more fine-grained exclusion.
178ba71 [Marcelo Vanzin] Oops.
75b2375 [Marcelo Vanzin] Exclude VertexRDD in MiMA.
a45a62c [Marcelo Vanzin] Work around MIMA warning.
1d8a670 [Marcelo Vanzin] Re-group jetty exclusion.
0e8e909 [Marcelo Vanzin] Ignore ml, don't ignore graphx.
cef4603 [Marcelo Vanzin] Indentation.
296cf82 [Marcelo Vanzin] [SPARK-6371] [build] Update version to 1.4.0-SNAPSHOT.

Option 1 of 2: Convert spark-parent module name to spark-parent_2.10 / spark-parent_2.11

Author: Sean Owen <sowen@cloudera.com>

Closes #4912 from srowen/SPARK-6182.1 and squashes the following commits:

eff60de [Sean Owen] Convert spark-parent module name to spark-parent_2.10 / spark-parent_2.11

Published Kafka-assembly JAR was empty in 1.3.0-RC1
This is because the maven build generated two Jars-
1. an empty JAR file (since kafka-assembly has no code of its own)
2. a assembly JAR file containing everything in a different location as 1
The maven publishing plugin uploaded 1 and not 2.
Instead if 2 is not configure to generate in a different location, there is only 1 jar containing everything, which gets published.

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #4753 from tdas/SPARK-5993 and squashes the following commits:

c390db8 [Tathagata Das] Fix assembly jar location of kafka-assembly

This PR brings the Python API for Spark Streaming Kafka data source.

```
    class KafkaUtils(__builtin__.object)
     |  Static methods defined here:
     |
     |  createStream(ssc, zkQuorum, groupId, topics, storageLevel=StorageLevel(True, True, False, False,
2), keyDecoder=<function utf8_decoder>, valueDecoder=<function utf8_decoder>)
     |      Create an input stream that pulls messages from a Kafka Broker.
     |
     |      :param ssc:  StreamingContext object
     |      :param zkQuorum:  Zookeeper quorum (hostname:port,hostname:port,..).
     |      :param groupId:  The group id for this consumer.
     |      :param topics:  Dict of (topic_name -> numPartitions) to consume.
     |                      Each partition is consumed in its own thread.
     |      :param storageLevel:  RDD storage level.
     |      :param keyDecoder:  A function used to decode key
     |      :param valueDecoder:  A function used to decode value
     |      :return: A DStream object
```
run the example:

```
bin/spark-submit --driver-class-path external/kafka-assembly/target/scala-*/spark-streaming-kafka-assembly-*.jar examples/src/main/python/streaming/kafka_wordcount.py localhost:2181 test
```

Author: Davies Liu <davies@databricks.com>
Author: Tathagata Das <tdas@databricks.com>

Closes #3715 from davies/kafka and squashes the following commits:

d93bfe0 [Davies Liu] Update make-distribution.sh
4280d04 [Davies Liu] address comments
e6d0427 [Davies Liu] Merge branch 'master' of github.com:apache/spark into kafka
f257071 [Davies Liu] add tests for null in RDD
23b039a [Davies Liu] address comments
9af51c4 [Davies Liu] Merge branch 'kafka' of github.com:davies/spark into kafka
a74da87 [Davies Liu] address comments
dc1eed0 [Davies Liu] Update kafka_wordcount.py
31e2317 [Davies Liu] Update kafka_wordcount.py
370ba61 [Davies Liu] Update kafka.py
97386b3 [Davies Liu] address comment
2c567a5 [Davies Liu] update logging and comment
33730d1 [Davies Liu] Merge branch 'master' of github.com:apache/spark into kafka
adeeb38 [Davies Liu] Merge pull request #3 from tdas/kafka-python-api
aea8953 [Tathagata Das] Kafka-assembly for Python API
eea16a7 [Davies Liu] refactor
f6ce899 [Davies Liu] add example and fix bugs
98c8d17 [Davies Liu] fix python style
5697a01 [Davies Liu] bypass decoder in scala
048dbe6 [Davies Liu] fix python style
75d485e [Davies Liu] add mqtt
07923c4 [Davies Liu] support kafka in Python