YARN-467. Modify public distributed cache to localize files such that no local directory hits unix file count limits and thus prevent job failures. Contributed by Omkar Vinit Joshi.
svn merge --ignore-ancestry -c 1463823 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1463824 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5117. Changed MRClientProtocolPBClientImpl to be closeable and thus fix failures in renewal of HistoryServer's delegations tokens. Contributed by Siddharth Seth.
svn merge --ignore-ancestry -c 1463828 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1463829 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/branch-2' into branch-2-gd
Merge remote branch 'origin/branch-2-gd' into fb-YARN-474-branch-2-gd