YARN-1678. Fair scheduler gabs incessantly about reservations (Sandy Ryza)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1571469 13f79535-47bb-0310-9956-ffa450edef68
YARN-1686. Fixed NodeManager to properly handle any errors during re-registration after a RESYNC and thus avoid hanging. Contributed by Rohith Sharma.
svn merge --ignore-ancestry -c 1571474 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1571475 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5776 Support 'hedged' reads in DFSClient (Liang Xie via stack)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1571479 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5761. Added a simple log message to denote when encrypted shuffle is on in the shuffle-handler. Contributed by Jian He.
svn merge --ignore-ancestry -c 1571514 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1571515 13f79535-47bb-0310-9956-ffa450edef68
YARN-1734. Fixed ResourceManager to update the configurations when it transits from standby to active mode so as to assimilate any changes that happened while it was in standby mode. Contributed by Xuan Gong.
svn merge --ignore-ancestry -c 1571539 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1571540 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5922. Merging r1571542 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1571543 13f79535-47bb-0310-9956-ffa450edef68