Merging with spark upstream changes.

README.md

assembly/pom.xml

bagel/pom.xml

bin/slaves.sh

bin/spark-daemon.sh

bin/spark-daemons.sh

bin/stop-slaves.sh

core/pom.xml

...ava/org/apache/spark/network/netty/FileClientHandler.java

...ava/org/apache/spark/network/netty/FileServerHandler.java

core/src/main/scala/org/apache/spark/Aggregator.scala

...ain/scala/org/apache/spark/BlockStoreShuffleFetcher.scala

core/src/main/scala/org/apache/spark/CacheManager.scala

core/src/main/scala/org/apache/spark/FutureAction.scala

...c/main/scala/org/apache/spark/InterruptibleIterator.scala

core/src/main/scala/org/apache/spark/MapOutputTracker.scala

core/src/main/scala/org/apache/spark/ShuffleFetcher.scala

core/src/main/scala/org/apache/spark/SparkContext.scala

core/src/main/scala/org/apache/spark/SparkHadoopWriter.scala

core/src/main/scala/org/apache/spark/TaskContext.scala