Merge r1529251 from trunk to branch-2 for YARN-1232. Configuration to support multiple RMs (Karthik Kambatla via bikas)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1529285 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1529296 FIXES: HADOOP-9225. Cover package org.apache.hadoop.compress.Snappy. Contributed by Vadim Bondarev, Andrey Klochkov and Nathan Roberts


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1529301 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5300. Merge change r1529294 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1529305 13f79535-47bb-0310-9956-ffa450edef68
YARN-1253. Changes to LinuxContainerExecutor to run containers as a single dedicated user in non-secure mode. (rvs via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1529326 13f79535-47bb-0310-9956-ffa450edef68