(Ported from https://github.com/apache/incubator-spark/pull/637 )

Author: Sean Owen <sowen@cloudera.com>

Closes #31 from srowen/SPARK-1084.1 and squashes the following commits:

6c4a32c [Sean Owen] Suppress warnings about legitimate unchecked array creations, or change code to avoid it
f35b833 [Sean Owen] Fix two misc javadoc problems
254e8ef [Sean Owen] Fix one new style error introduced in scaladoc warning commit
5b2fce2 [Sean Owen] Fix scaladoc invocation warning, and enable javac warnings properly, with plugin config updates
007762b [Sean Owen] Remove dead scaladoc links
b8ff8cb [Sean Owen] Replace deprecated Ant <tasks> with <target>

It looks this just requires taking out the checks.

I verified that, with the patch, I was able to run spark-shell through yarn without setting the environment variable.

Author: Sandy Ryza <sandy@cloudera.com>

Closes #553 from sryza/sandy-spark-1053 and squashes the following commits:

b037676 [Sandy Ryza] SPARK-1053.  Don't require SPARK_YARN_APP_JAR

Version number to 1.0.0-SNAPSHOT

Since 0.9.0-incubating is done and out the door, we shouldn't be building 0.9.0-incubating-SNAPSHOT anymore.

@pwendell

Author: Mark Hamstra <markhamstra@gmail.com>

== Merge branch commits ==

commit 1b00a8a7c1a7f251b4bb3774b84b9e64758eaa71
Author: Mark Hamstra <markhamstra@gmail.com>
Date:   Wed Feb 5 09:30:32 2014 -0800

    Version number to 1.0.0-SNAPSHOT

spark on yarn - yarn-client mode doesn't always exit immediately

https://spark-project.atlassian.net/browse/SPARK-1049

If you run in the yarn-client mode but you don't get all the workers you requested right away and then you exit your application, the application master stays around until it gets the number of workers you initially requested. This is a waste of resources.  The AM should exit immediately upon the client going away.

This fix simply checks to see if the driver closed while its waiting for the initial # of workers.

Author: Thomas Graves <tgraves@apache.org>

== Merge branch commits ==

commit 03f40a62584b6bdd094ba91670cd4aa6afe7cd81
Author: Thomas Graves <tgraves@apache.org>
Date:   Fri Jan 31 11:23:10 2014 -0600

    spark on yarn - yarn-client mode doesn't always exit immediately

Incorporate Tom's comments - update doc and code to reflect that core requests may not always be honored

-) Only change simple return statements at the end of method
-) Ignore the complex if-else check
-) Ignore the ones inside synchronized

- Got rid of global SparkContext.globalConf
- Pass SparkConf to serializers and compression codecs
- Made SparkConf public instead of private[spark]
- Improved API of SparkContext and SparkConf
- Switched executor environment vars to be passed through SparkConf
- Fixed some places that were still using system properties
- Fixed some tests, though others are still failing

This still fails several tests in core, repl and streaming, likely due
to properties not being set or cleared correctly (some of the tests run
fine in isolation).