Merge pull request #415 from pwendell/shuffle-compress

Enable compression by default for spills
Merge remote-tracking branch 'upstream/master' into code-style
Merge remote-tracking branch 'upstream/master' into sparsesvd
Merge remote-tracking branch 'apache/master' into filestream-fix

Conflicts:
	streaming/src/main/scala/org/apache/spark/streaming/dstream/DStream.scala
Fixed loose ends in docs.
Merge pull request #416 from tdas/filestream-fix

Removed unnecessary DStream operations and updated docs

Removed StreamingContext.registerInputStream and registerOutputStream - they were useless. InputDStream has been made to register itself, and just registering a DStream as output stream cause RDD objects to be created but the RDDs will not be computed at all.. Also made DStream.register() private[streaming] for the same reasons.

Updated docs, specially added package documentation for streaming package.

Also, changed NetworkWordCount's input storage level to use MEMORY_ONLY, replication on the local machine causes warning messages (as replication fails) which is scary for a new user trying out his/her first example.
Modifications as suggested in PR feedback-

- more variants of mapPartitions added to JavaRDDLike
- move setGenerator to JavaRDDLike
- clean up
Add missing header files
Merge pull request #420 from pwendell/header-files

Add missing header files
Added parentheses for that getDouble() also has side effect
Improving the graphx-programming-guide.
Merge pull request #423 from jegonzal/GraphXProgrammingGuide

Improving the graphx-programming-guide

This PR will track a few minor improvements to the content and formatting of the graphx-programming-guide.
Additional edits for clarity in the graphx programming guide.
Broadcast variable visibility change & doc update.

Note that previously Broadcast class was accidentally marked as private[spark]. It needs to be public
for broadcast variables to work. Also exposing the broadcast varaible id.
Updated API doc for Accumulable and Accumulator.
Added package doc for the Java API.
Added license header for package.scala in the Java API package.
Maintain Serializable API compatibility by reverting back to java.io.Serializable for Broadcast and Accumulator.
Fixed a typo in JavaSparkContext's API doc.
Don't clone records for text files