Add RDD checkpointing to Python API.
Add checkpointFile() and more tests to PySpark.
Update checkpointing API docs in Python/Java.
Clean up setup code in PySpark checkpointing tests
Fix PythonPartitioner equality; see SPARK-654.

PythonPartitioner did not take the Python-side partitioning function
into account when checking for equality, which might cause problems
in the future.
Merge pull request #390 from JoshRosen/spark-654

Fix PythonPartitioner equality
Merge pull request #389 from JoshRosen/python_rdd_checkpointing

Add checkpointing to the Python API
Add Maven build file for streaming, and fix some issues in SBT file

As part of this, changed our Scala 2.9.2 Kafka library to be available
as a local Maven repository, following the example in
(http://blog.dub.podval.org/2010/01/maven-in-project-repository.html)
Update run script to deal with change to build of REPL shaded JAR
Log remote lifecycle events in Akka for easier debugging
Merge branch 'master' of https://github.com/mesos/spark