add compression codec trait and snappy compression
fix dependencies
Enhance job ui in spark ui system with adding pool information
Building spark assembly for further consumption of the Spark project with a deployed cluster
Made RegressionModel serializable and added unit tests to make sure predict methods would work.
Use a different validation dataset for Logistic Regression prediction testing.
Tracks task start events and shows number of active tasks on Executor UI
Merge pull request #723 from rxin/mllib

Made RegressionModel serializable and added unit tests to make sure predict methods would work.
Adds/removes active tasks only once
SPARK-829: scheduler shouldn't hang if a task contains unserializable objects in its closure.
Scheduler code style cleanup.
SPARK-829: scheduler shouldn't hang if a task contains unserializable objects in its closure.
Replaces Seq with HashSet, removes redundant import
Modifies instead of copies HashSets, fixes comment style
Merge pull request #725 from karenfeng/task-start

Creates task start events
Small bug fix
Moved non-serializable closure catching exception from submitStage to submitMissingTasks
Added comments on task closure serialization.
Moved non-serializable closure catching exception from submitStage to submitMissingTasks
Merge pull request #726 from rxin/spark-826

SPARK-829: scheduler shouldn't hang if a task contains unserializable objects in its closure