Merge branch 'master' into fast-map

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

...la/org/apache/spark/deploy/master/ApplicationSource.scala

...n/scala/org/apache/spark/deploy/master/MasterSource.scala

...n/scala/org/apache/spark/deploy/worker/WorkerSource.scala

...main/scala/org/apache/spark/executor/ExecutorSource.scala

.../main/scala/org/apache/spark/scheduler/DAGScheduler.scala

...scala/org/apache/spark/scheduler/DAGSchedulerSource.scala

...n/scala/org/apache/spark/scheduler/SparkListenerBus.scala

...in/scala/org/apache/spark/serializer/KryoSerializer.scala

...n/scala/org/apache/spark/storage/BlockManagerSource.scala

...scala/org/apache/spark/scheduler/SparkListenerSuite.scala

...ala/org/apache/spark/serializer/KryoSerializerSuite.scala

docs/mllib-guide.md

docs/python-programming-guide.md

...ain/scala/org/apache/spark/mllib/recommendation/ALS.scala

...a/org/apache/spark/mllib/recommendation/JavaALSSuite.java

...cala/org/apache/spark/mllib/recommendation/ALSSuite.scala

python/pyspark/rdd.py