In CHANGES.txt, move HDFS-4908 and HDFS-4645 to 2.1.0-beta.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1502009 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-4374. Fix child task environment variable config and add support for Windows. Contributed by Chuan Liu.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1502046 13f79535-47bb-0310-9956-ffa450edef68
updating CHANGES.txt after committing MAPREDUCE-5333,HADOOP-9661,HADOOP-9355,HADOOP-9673,HADOOP-9414,HADOOP-9416,HDFS-4797,YARN-866,YARN-736,YARN-883 to 2.1-beta branch

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1502075 13f79535-47bb-0310-9956-ffa450edef68
YARN-569. Add support for requesting and enforcing preemption requests via
a capacity monitor. Contributed by Carlo Curino, Chris Douglas


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1502083 13f79535-47bb-0310-9956-ffa450edef68