YARN-1295. In UnixLocalWrapperScriptBuilder, using bash -c can cause Text file busy errors. (Sandy Ryza)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1532532 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5330. fix readdir and readdirplus for large directories. Contributed by Brandon Li

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1532539 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5130. Add test for snapshot related FsShell and DFSAdmin commands. Contributed by Binglin Chang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1532580 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