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/trunk@1467244 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4477. Secondary namenode may retain old tokens. Contributed by Daryn Sharp.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1467307 13f79535-47bb-0310-9956-ffa450edef68