SAMZA-337; compress configs passed through environment variables in YARN
Merge branch 'master' into s71

Conflicts:
	samza-core/src/main/scala/org/apache/samza/container/SamzaContainer.scala
	samza-core/src/main/scala/org/apache/samza/job/ShellCommandBuilder.scala
	samza-core/src/main/scala/org/apache/samza/util/Util.scala