Merge pull request #170 from harveyfeng/rddtable

Remove table from Shark and Hive metadata if the Spark job for RDD => Shark table RDD transformation fails.
A smarter execution strategy for limit.
Fixed a bug in numPartsToTry calculation.
Overestimate by 50%.
Merge branch 'limit2' into rddtable
Merge branch 'rddtable' of github.com:amplab/shark into rddtable
Increase # of types in RDDTable#apply() to 22, the limit for Scala's tuple length.
Bump up version to Spark 0.9.