HADOOP-9231. Parametrize staging URL for the uniformity of distributionManagement. Contributed by Konstantin Boudnik.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1437140 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-9231. Add missing CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1437143 13f79535-47bb-0310-9956-ffa450edef68
YARN-277. Use AMRMClient in DistributedShell to exemplify the approach. Contributed by Bikas Saha

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1437156 13f79535-47bb-0310-9956-ffa450edef68
Merge remote-tracking branch 'apache/trunk' into MAPREDUCE-4838
YARN-231. RM Restart - Add FS-based persistent store implementation for RMStateStore. Contributed by Bikas Saha

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1437245 13f79535-47bb-0310-9956-ffa450edef68
Incorporate Sid's comments and fix the test cases.
Remove the unnecessary changes.
Merge remote-tracking branch 'apache/trunk' into MAPREDUCE-4838
Fix some formating issues.