re-enable tachyon.
re-enable tachyon.

If it doesn't work with Spark 1.4.1, re-disable it.

dmtran-osc/spark-ec2,dm-tran/spark-ec2,dm-tran/spark-ec2,dm-tran/spark-ec2,dmtran-osc/spark-ec2,dmtran-osc/spark-ec2