Merge pull request #494 from mesos/streaming

core/src/main/scala/spark/rdd/CheckpointRDD.scala

core/src/main/scala/spark/util/MetadataCleaner.scala

core/src/test/scala/spark/CheckpointSuite.scala

docs/configuration.md

docs/python-programming-guide.md

docs/streaming-custom-receivers.md

docs/streaming-programming-guide.md

examples/pom.xml

...in/java/spark/streaming/examples/JavaFlumeEventCount.java

...n/java/spark/streaming/examples/JavaNetworkWordCount.java

...c/main/java/spark/streaming/examples/JavaQueueStream.java

.../main/scala/spark/streaming/examples/ActorWordCount.scala

.../main/scala/spark/streaming/examples/KafkaWordCount.scala

...ain/scala/spark/streaming/examples/NetworkWordCount.scala

.../main/scala/spark/streaming/examples/RawNetworkGrep.scala

...n/scala/spark/streaming/examples/TwitterAlgebirdCMS.scala

...n/scala/spark/streaming/examples/TwitterAlgebirdHLL.scala

...n/scala/spark/streaming/examples/TwitterPopularTags.scala

...main/scala/spark/streaming/examples/ZeroMQWordCount.scala

...spark/streaming/examples/clickstream/PageViewStream.scala