HDFS-5300. FSNameSystem#deleteSnapshot() should not check owner in case of permissions disabled. Contributed by Vinay.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1529294 13f79535-47bb-0310-9956-ffa450edef68
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/trunk@1529296 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/trunk@1529325 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-HDFS-4312-trunk-gd