## What changes were proposed in this pull request?

Per conversation on dev list, add missing modernizr license.
Specify "2014 and onwards" in copyright statement.

## How was this patch tested?

(none required)

Author: Sean Owen <sowen@cloudera.com>

Closes #13510 from srowen/ModernizrLicense.

## What changes were proposed in this pull request?

This PR continues the work from #11871 with the following changes:
* load English stopwords as default
* covert stopwords to list in Python
* update some tests and doc

## How was this patch tested?

Unit tests.

Closes #11871

cc: burakkose srowen

Author: Burak Köse <burakks41@gmail.com>
Author: Xiangrui Meng <meng@databricks.com>
Author: Burak KOSE <burakks41@gmail.com>

Closes #12843 from mengxr/SPARK-14050.

[SPARK-13874][DOC] Remove docs of streaming-akka, streaming-zeromq, streaming-mqtt and streaming-twitter

## What changes were proposed in this pull request?

This PR removes all docs about the old streaming-akka, streaming-zeromq, streaming-mqtt and streaming-twitter projects since I have already copied them to https://github.com/spark-packages

Also remove mqtt_wordcount.py that I forgot to remove previously.

## How was this patch tested?

Jenkins PR Build.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #11824 from zsxwing/remove-doc.

In the course of https://issues.apache.org/jira/browse/LEGAL-226 it came to light that the guidance at http://www.apache.org/dev/licensing-howto.html#permissive-deps means that permissively-licensed dependencies has a different interpretation than we (er, I) had been operating under. "pointer ... to the license within the source tree" specifically means a copy of the license within Spark's distribution, whereas at the moment, Spark's LICENSE has a pointer to the project's license in the other project's source tree.

The remedy is simply to inline all such license references (i.e. BSD/MIT licenses) or include their text in "licenses" subdirectory and point to that.

Along the way, we can also treat other BSD/MIT licenses, whose text has been inlined into LICENSE, in the same way.

The LICENSE file can continue to provide a helpful list of BSD/MIT licensed projects and a pointer to their sites. This would be over and above including license text in the distro, which is the essential thing.

Author: Sean Owen <sowen@cloudera.com>

Closes #8919 from srowen/SPARK-10833.