YARN-2582. Fixed Log CLI and Web UI for showing aggregated logs of LRS. Contributed Xuan Gong.

(cherry picked from commit e90718fa5a0e7c18592af61534668acebb9db51b)
HDFS-7266. HDFS Peercache enabled check should not lock on object (awang via cmccabe)
(cherry picked from commit 4799570dfdb7987c2ac39716143341e9a3d9b7d2)
HDFS-7154. Fix returning value of starting reconfiguration task (Lei Xu via Colin P. McCabe)
(cherry picked from commit 7aab5fa1bd9386b036af45cd8206622a4555d74a)
YARN-2701. Potential race condition in startLocalizer when using LinuxContainerExecutor. Contributed by Xuan Gong
(cherry picked from commit 2839365f230165222f63129979ea82ada79ec56e)
Missing file for YARN-2701
(cherry picked from commit 4fa1fb3193bf39fcb1bd7f8f8391a78f69c3c302)
Missing file for YARN-1879
(cherry picked from commit 4a78a752286effbf1a0d8695325f9d7464a09fb4)
YARN-2717. Avoided duplicate logging when container logs are not found. Contributed by Xuan Gong.

(cherry picked from commit 171f2376d23d51b61b9c9b3804ee86dbd4de033a)
Merge remote-tracking branch 'remotes/origin/branch-2' into branch-2