Interchange order of materialization and table caching so we can clean up RDDs on failure during table creation
Merge branch 'overload' of github.com:harsha2010/shark into unionrdd

Conflicts:
	src/main/scala/shark/execution/MemoryStoreSinkOperator.scala
Updated test to prevent log4j from deadlocking the entire test suite in some configurations.
Merge branch 'master' of https://github.com/amplab/shark into 0.8-merge