Allow spark on yarn to be run from HDFS. Allows the spark.jar, app.jar, and log4j.properties to be put into hdfs.
add tachyon module
expose UI port only
Fix bug JIRA-923
cut lines to less than 100
fix format error
Add mockito to the sbt build
Merge pull request #156 from haoyuan/master

add tachyon module
Enable stopping and starting a spot cluster
Made block generator thread safe to fix Kafka bug.
Merge pull request #164 from tdas/kafka-fix

Made block generator thread safe to fix Kafka bug.

This is a very important bug fix. Data can and was being lost in the kafka due to this.
Merge pull request #160 from xiajunluan/JIRA-923

Fix bug JIRA-923

Fix column sort issue in UI for JIRA-923.
https://spark-project.atlassian.net/browse/SPARK-923

Conflicts:
	core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala
	core/src/main/scala/org/apache/spark/ui/jobs/StageTable.scala
Merge pull request #153 from ankurdave/stop-spot-cluster

Enable stopping and starting a spot cluster

Clusters launched using `--spot-price` contain an on-demand master and spot slaves. Because EC2 does not support stopping spot instances, the spark-ec2 script previously could only destroy such clusters.

This pull request makes it possible to stop and restart a spot cluster.
* The `stop` command works as expected for a spot cluster: the master is stopped and the slaves are terminated.
* To start a stopped spot cluster, the user must invoke `launch --use-existing-master`. This launches fresh spot slaves but resumes the existing master.
Merge pull request #137 from tgravescs/sparkYarnJarsHdfsRebase

Allow spark on yarn to be run from HDFS.

Allows the spark.jar, app.jar, and log4j.properties to be put into hdfs.  Allows you to specify the files on a different hdfs cluster and it will copy them over. It makes sure permissions are correct and makes sure to put things into public distributed cache so they can be reused amongst users if their permissions are appropriate.  Also add a bit of error handling for missing arguments.