Merge r1618294 from trunk. YARN-2389. Added functionality for schedulers to kill all applications in a queue. Contributed by Subramaniam Venkatraman Krishnan

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1618295 13f79535-47bb-0310-9956-ffa450edef68