Merge branch 'master' into mos-bt

Conflicts:
	Makefile
	run
	src/scala/spark/Broadcast.scala
	src/scala/spark/Executor.scala
	src/scala/spark/HdfsFile.scala
	src/scala/spark/MesosScheduler.scala
	src/scala/spark/RDD.scala
	src/scala/spark/SparkContext.scala
	src/scala/spark/Split.scala
	src/scala/spark/Utils.scala
	src/scala/spark/repl/SparkInterpreter.scala
	third_party/mesos.jar