Changed method name of createReceiver to getReceiver as it is not intended to be a factory.
actor as receiver
Improved document comment in example
Taking FeederActor out as seperate program
Merge branch 'streaming' into ScrapCodes-streaming-actor

Conflicts:
	docs/plugin-custom-receiver.md
	streaming/src/main/scala/spark/streaming/StreamingContext.scala
	streaming/src/main/scala/spark/streaming/dstream/KafkaInputDStream.scala
	streaming/src/main/scala/spark/streaming/dstream/PluggableInputDStream.scala
	streaming/src/main/scala/spark/streaming/receivers/ActorReceiver.scala
	streaming/src/test/scala/spark/streaming/InputStreamsSuite.scala