HADOOP-10273. Update CHANGES.txt to reflect new target version is 2.3 (merged r1565453 from trunk to branch-2)

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MAPREDUCE-5744. Job hangs because RMContainerAllocator.preemptReduce() violates the comparator contract (Gera Shegalov via kasha)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565479 13f79535-47bb-0310-9956-ffa450edef68
YARN-1689. Made RMAppAttempt get killed when RMApp is at ACCEPTED. Contributed by Vinod Kumar Vavilapalli.
svn merge --ignore-ancestry -c 1565497 ../../trunk/


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svn merge -c 1565505 merging from trunk to branch-2 to fix:HDFS-5807. TestBalancerWithNodeGroup.testBalancerWithNodeGroup fails intermittently.

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HADOOP-10330. Merging r1565507 from trunk to branch-2.

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YARN-1665. Simplify the configuration of RM HA by having better default values. Contributed by Xuan Gong.
svn merge --ignore-ancestry -c 1565517 ../../trunk/


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YARN-1660. Simplified the RM HA configuration to accept and be able to simply depend just on
configuration properties of the form yarn.resourcemanager.hostname.RMID and use the default
ports for all service addresses. Contributed by Xuan Gong.
svn merge --ignore-ancestry -c 1565523 ../../trunk/


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