HADOOP-9231. Merge 1437140 and 1437143 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1437144 13f79535-47bb-0310-9956-ffa450edef68
merge -c 1437156 from trunk to branch-2 to fix YARN-277. Use AMRMClient in DistributedShell to exemplify the approach. Contriubed by Bikas Saha

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1437159 13f79535-47bb-0310-9956-ffa450edef68