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/branches/branch-2@1493987 13f79535-47bb-0310-9956-ffa450edef68
merge YARN-805 from trunk. 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/branches/branch-2@1493993 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.
svn merge --ignore-ancestry -c 1494017 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1494018 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4818. Merging change r1494023 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1494024 13f79535-47bb-0310-9956-ffa450edef68
Merge -c 1494027 from trunk to branch-2 to fix YARN-840. Moved ProtoUtils to yarn.api.records.pb.impl. Contributed by Jian He.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1494029 13f79535-47bb-0310-9956-ffa450edef68
YARN-841. Move Auxiliary service to yarn-api, annotate and document it. Contributed by Vinod Kumar Vavilapalli.
svn merge --ignore-ancestry -c 1494031 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1494032 13f79535-47bb-0310-9956-ffa450edef68
Merge -c 1494035 from trunk to branch-2 to fix YARN-799. Fix CgroupsLCEResourcesHandler to use /tasks instead of /cgroup.procs. Contributed by Chris Riccomini.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1494036 13f79535-47bb-0310-9956-ffa450edef68
YARN-846.  Move pb Impl classes from yarn-api to yarn-common. Contributed by Jian He.
svn merge --ignore-ancestry -c 1494052 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1494053 13f79535-47bb-0310-9956-ffa450edef68