HDFS-4626. ClientProtocol#getLinkTarget should throw an exception for non-symlink and non-existent paths.  (Andrew Wang via cmccabe)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1493980 13f79535-47bb-0310-9956-ffa450edef68
YARN-805. Fix javadoc and annotations on classes in the yarn-api package. Contributed by Jian He.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1493992 13f79535-47bb-0310-9956-ffa450edef68
YARN-834. Fixed annotations for yarn-client module, reorganized packages and clearly differentiated *Async apis. Contributed by Arun C Murthy and Zhijie Shen.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1494017 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-HDFS-4311-trunk-gd