HDFS-6781. Separate HDFS commands from CommandsManual.apt.vm. (Contributed by Akira Ajisaka)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1616576 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6781. Add file missed in previous commit.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1616577 13f79535-47bb-0310-9956-ffa450edef68
Merge r1616580 from trunk. YARN-2008. Fixed CapacityScheduler to calculate headroom based on max available capacity instead of configured max capacity. Contributed by Craig Welch

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1616581 13f79535-47bb-0310-9956-ffa450edef68