add ensime
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
bug fix for javadoc
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
support customized java options for master, worker, executor, repl shell
Add RDD.subtract.

Instead of reusing the cogroup primitive, this adds a SubtractedRDD
that knows it only needs to keep rdd1's values (per split) in memory.
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'mesos'
Merge branch 'master' into subtract
Update for split->partition rename.
Add subtract to JavaRDD, JavaDoubleRDD, and JavaPairRDD.