upgraded sbt version, sbt plugins and some library dependencies to latest stable version
added SPARK_WORKER_INSTANCES : allows spawning multiple worker instances/processes on every slave machine
spark instance number must be present in log filename to prevent multiple workers from overriding each other's logs
merge master
Bumping Algebird version in examples now that it supports JDK 1.6
Update build to Scala 2.9.3
Merge pull request #554 from andyk/scala2.9.3

Fixes SPARK-723 - Update build to Scala 2.9.3
Merge pull request #552 from MLnick/master

Bumping version for Twitter Algebird to latest
Update Scala version in docs
Fix deprecated warning
Updated link to SBT
Merge remote-tracking branch 'kalpit/master'

Conflicts:
	project/SparkBuild.scala
Fix compile warning
Fixed a bug with zip
Merge branch 'master' of https://github.com/mesos/spark
Merged master