Merge pull request #317 from harveyfeng/branch-0.9

Test 0.9.1
Merge pull request #314 from twleung0507/master

Fixed mismatched ordering after multiple data load
Merge pull request #316 from aarondav/master

Extract Tachyon interface to allow pluggable off-heap storage clients
Merge pull request #311 from CrazyJvm/patch-1

fix "get scala version error"  ---  issue #Shark-219#
Added python table rdd
Fixed bug
1 pickler per thread
PR changes
Merge pull request #318 from ahirreddy/master

PythonTableRDD