SPARK-1700: Close socket file descriptors on task completion

This will ensure that sockets do not build up over the course of a job, and that cancellation successfully cleans up sockets.

Tested in standalone mode. More file descriptors spawn than expected (around 1000ish rather than the expected 8ish) but they do not pile up between runs, or as high as before (where they went up to around 5k).

Author: Aaron Davidson <aaron@databricks.com>

Closes #623 from aarondav/pyspark2 and squashes the following commits:

0ca13bb [Aaron Davidson] SPARK-1700: Close socket file descriptors on task completion
Update SchemaRDD.scala

Modify spelling errors

Author: ArcherShao <ArcherShao@users.noreply.github.com>

Closes #619 from ArcherShao/patch-1 and squashes the following commits:

2957195 [ArcherShao] Update SchemaRDD.scala
[WIP] SPARK-1676: Cache Hadoop UGIs by default to prevent FileSystem leak

Move the doAs in Executor higher up so that we only have 1 ugi and aren't leaking filesystems.
Fix spark on yarn to work when the cluster is running as user "yarn" but the clients are launched as the user and want to read/write to hdfs as the user.

Note this hasn't been fully tested yet.  Need to test in standalone mode.

Putting this up for people to look at and possibly test.  I don't have access to a mesos cluster.

This is alternative to https://github.com/apache/spark/pull/607

Author: Thomas Graves <tgraves@apache.org>

Closes #621 from tgravescs/SPARK-1676 and squashes the following commits:

244d55a [Thomas Graves] fix line length
44163d4 [Thomas Graves] Rework
9398853 [Thomas Graves] change to have doAs in executor higher up.
SPARK-1663. Corrections for several compile errors in streaming code examples, and updates to follow API changes

I gave the Streaming code examples, both Scala and Java, a test run today. I turned up a number of small errors, mostly compile errors in the Java examples. There were a few typos in the Scala too.

I also took the liberty of adding things like imports, since in several cases they are not obvious. Feel free to push back on some changes.

There's one thing I haven't quite addressed in the changes. `JavaPairDStream` uses the Java API version of `Function2` in almost all cases, as `JFunction2`. However it uses `scala.Function2` in:

```
  def reduceByKeyAndWindow(reduceFunc: Function2[V, V, V], windowDuration: Duration)
  :JavaPairDStream[K, V] = {
    dstream.reduceByKeyAndWindow(reduceFunc, windowDuration)
  }
```

Is that a typo?

Also, in Scala, I could not get this to compile:
```
val windowedWordCounts = pairs.reduceByKeyAndWindow(_ + _, Seconds(30), Seconds(10))
error: missing parameter type for expanded function ((x$1, x$2) => x$1.$plus(x$2))
```

You can see my fix below but am I missing something?

Otherwise I can say these all worked for me!

Author: Sean Owen <sowen@cloudera.com>

Closes #589 from srowen/SPARK-1663 and squashes the following commits:

65a906b [Sean Owen] Corrections for several compile errors in streaming code examples, and updates to follow API changes
[Bugfix] Tachyon file cleanup logical error

Should lookup `shutdownDeleteTachyonPaths` instead of `shutdownDeletePaths`. Together with a minor style clean up: `find {...}.isDefined` to `exists {...}`.

Author: Cheng Lian <lian.cs.zju@gmail.com>

Closes #575 from liancheng/tachyonFix and squashes the following commits:

deb8f31 [Cheng Lian] Fixed logical error in when cleanup Tachyon files and minor style cleanup
SPARK-1689 AppClient should indicate app is dead() when removed

Previously, we indicated disconnected(), which keeps the application in a limbo state where it has no executors but thinks it will get them soon.

This is a bug fix that hopefully can be included in 1.0.

Author: Aaron Davidson <aaron@databricks.com>

Closes #605 from aarondav/appremoved and squashes the following commits:

bea02a2 [Aaron Davidson] SPARK-1689 AppClient should indicate app is dead() when removed
EC2 configurable workers

Added option to configure number of worker instances and to set SPARK_MASTER_OPTS

Depends on: https://github.com/mesos/spark-ec2/pull/46

Author: Allan Douglas R. de Oliveira <allan@chaordicsystems.com>

Closes #612 from douglaz/ec2_configurable_workers and squashes the following commits:

d6c5d65 [Allan Douglas R. de Oliveira] Added master opts parameter
6c34671 [Allan Douglas R. de Oliveira] Use number of worker instances as string on template
ba528b9 [Allan Douglas R. de Oliveira] Added SPARK_WORKER_INSTANCES parameter
[SQL] Better logging when applying rules.

Author: Michael Armbrust <michael@databricks.com>

Closes #616 from marmbrus/ruleLogging and squashes the following commits:

39c09fe [Michael Armbrust] Fix off by one error.
5af3537 [Michael Armbrust] Better logging when applying rules.
Whitelist Hive Tests

This is ready when Jenkins is.

Author: Michael Armbrust <michael@databricks.com>

Closes #596 from marmbrus/moreTests and squashes the following commits:

85be703 [Michael Armbrust] Blacklist MR required tests.
35bc311 [Michael Armbrust] Add hive golden answers.
ede98fd [Michael Armbrust] More hive gitignore
da096ea [Michael Armbrust] update whitelist
The default version of yarn is equal to the hadoop version

This is a part of [PR 590](https://github.com/apache/spark/pull/590)

Author: witgo <witgo@qq.com>

Closes #626 from witgo/yarn_version and squashes the following commits:

c390631 [witgo] restore  the yarn dependency declarations
f8a4ad8 [witgo] revert remove the dependency of avro in yarn-alpha
2df6cf5 [witgo] review commit
a1d876a [witgo] review commit
20e7e3e [witgo] review commit
c76763b [witgo] The default value of yarn.version is equal to hadoop.version
SPARK-1658: Correctly identify if maven is installed and working

The current test is checking the exit code of "tail" rather than "mvn".
This new check will make sure that mvn is installed and was able to
execute the "version command".

Author: Rahul Singhal <rahul.singhal@guavus.com>

Closes #580 from rahulsinghaliitd/SPARK-1658 and squashes the following commits:

83c0313 [Rahul Singhal] SPARK-1658: Correctly identify if maven is installed and working
bf821b9 [Rahul Singhal] SPARK-1658: Correctly identify if maven is installed and working
SPARK-1663. (Addendum) Fix signature of one version of JavaPairRDDStream.reduceByKeyAndWindow()

It appears that one of these methods doesn't use `org.apache.spark.api.java.function.Function2` like all the others, but uses Scala's `Function2`.

Author: Sean Owen <sowen@cloudera.com>

Closes #633 from srowen/SPARK-1663.2 and squashes the following commits:

1e0232d [Sean Owen] Fix signature of one version of reduceByKeyAndWindow to use Java API Function2, as apparently intended
SPARK-1703 Warn users if Spark is run on JRE6 but compiled with JDK7.

This add some guards and good warning messages if users hit this issue. /cc @aarondav with whom I discussed parts of the design.

Author: Patrick Wendell <pwendell@gmail.com>

Closes #627 from pwendell/jdk6 and squashes the following commits:

a38a958 [Patrick Wendell] Code review feedback
94e9f84 [Patrick Wendell] SPARK-1703 Warn users if Spark is run on JRE6 but compiled with JDK7.
SPARK-1629. Addendum: Depend on commons lang3 (already used by tachyon) as it's used in ReplSuite, and return to use lang3 utility in Utils.scala

For consideration. This was proposed in related discussion: https://github.com/apache/spark/pull/569

Author: Sean Owen <sowen@cloudera.com>

Closes #635 from srowen/SPARK-1629.2 and squashes the following commits:

a442b98 [Sean Owen] Depend on commons lang3 (already used by tachyon) as it's used in ReplSuite, and return to use lang3 utility in Utils.scala
SPARK-1693: Most of the tests throw a java.lang.SecurityException when s...

...park built for hadoop 2.3.0 , 2.4.0

Author: witgo <witgo@qq.com>

Closes #628 from witgo/SPARK-1693_new and squashes the following commits:

e3af968 [witgo] Merge branch 'master' of https://github.com/apache/spark into SPARK-1693_new
dc63905 [witgo] SPARK-1693: Most of the tests throw a java.lang.SecurityException when spark built for hadoop 2.3.0 , 2.4.0
EC2 script should exit with non-zero code on UsageError

This is specially import because some ssh errors are raised as UsageError, preventing an automated usage of the script from detecting the failure.

Author: Allan Douglas R. de Oliveira <allan@chaordicsystems.com>

Closes #638 from douglaz/ec2_exit_code_fix and squashes the following commits:

5915e6d [Allan Douglas R. de Oliveira] EC2 script should exit with non-zero code on UsageError
SPARK-1710: spark-submit should print better errors than "InvocationTargetException"

Catching the InvocationTargetException, printing getTargetException.

Author: Sandeep <sandeep@techaddict.me>

Closes #630 from techaddict/SPARK-1710 and squashes the following commits:

834d79b [Sandeep] changes from srowen  suggestions
109d604 [Sandeep] SPARK-1710: spark-submit should print better errors than "InvocationTargetException"
Address SPARK-1717

I tested the change locally with Spark 0.9.1, but I can't test with 1.0.0 because there was no AMI for it at the time. It's a trivial fix, so it shouldn't cause any problems.

Author: msiddalingaiah <madhu@madhu.com>

Closes #641 from msiddalingaiah/master and squashes the following commits:

a4f7404 [msiddalingaiah] Address SPARK-1717
Updated doc for spark.closure.serializer to indicate only Java serializer work.

See discussion from http://apache-spark-developers-list.1001551.n3.nabble.com/bug-using-kryo-as-closure-serializer-td6473.html

Author: Reynold Xin <rxin@apache.org>

Closes #642 from rxin/docs-ser and squashes the following commits:

a507db5 [Reynold Xin] Use "Java" instead of default.
5eb8cdd [Reynold Xin] Updated doc for spark.closure.serializer to indicate only the default serializer work.
SPARK-1556. jets3t dep doesn't update properly with newer Hadoop versions

See related discussion at https://github.com/apache/spark/pull/468

This PR may still overstep what you have in mind, but let me put it on the table to start. Besides fixing the issue, it has one substantive change, and that is to manage Hadoop-specific things only in Hadoop-related profiles. This does _not_ remove `yarn.version`.

- Moves the YARN and Hadoop profiles together in pom.xml. Sorry that this makes the diff a little hard to grok but the changes are only as follows.
- Removes `hadoop.major.version`
- Introduce `hadoop-2.2` and `hadoop-2.3` profiles to control Hadoop-specific changes:
  - like the protobuf version issue - this was only 'solved' now by enabling YARN for 2.2+, which is really an orthogonal issue
  - like the jets3t version issue now
- Hadoop profiles set an appropriate default `hadoop.version`, that can be overridden
- _(YARN profiles in the parent now only exist to add the sub-module)_
- Fixes the jets3t dependency issue
 - and makes it a runtime dependency
 - and centralizes config of this guy in the parent pom
- Updates build docs
- Updates SBT build too
  - and fixes a regex problem along the way

Author: Sean Owen <sowen@cloudera.com>

Closes #629 from srowen/SPARK-1556 and squashes the following commits:

c3fa967 [Sean Owen] Fix hadoop-2.4 profile typo in doc
a2105fd [Sean Owen] Add hadoop-2.4 profile and don't set hadoop.version in profiles
274f4f9 [Sean Owen] Make jets3t a runtime dependency, and bring its exclusion up into parent config
bbed826 [Sean Owen] Use jets3t 0.9.0 for Hadoop 2.3+ (and correct similar regex issue in SBT build)
f21f356 [Sean Owen] Build changes to set up for jets3t fix