Merge -c 1467244 from trunk to branch-2 to fix YARN-412. Fixed FifoScheduler to check hostname of a NodeManager rather than its host:port during scheduling which caused incorrect locality for containers. Contributed by Roger Hoover.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1467245 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/branch-2' into branch-2-gd
Merge remote branch 'origin/branch-2-gd' into fb-HADOOP-9166-branch-2-gd