Merge -c 1471556 from trunk to branch-2 to fix MAPREDUCE-4737. Ensure that mapreduce APIs are semantically consistent with mapred API w.r.t Mapper.cleanup and Reducer.cleanup; in the sense that cleanup is now called even if there is an error. The old mapred API already ensures that Mapper.close and Reducer.close are invoked during error handling. Note that it is an incompatible change, however end-users can override Mapper.run and Reducer.run to get the old (inconsistent) behaviour. Contributed by Arun C. Murthy.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471557 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4151. Merge r1406006 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471567 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4209. Merge r1414447 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471574 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4334. Merge r1426429 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471582 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4296. Merge r1420700 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471590 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4339. Merge change r1465835 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471596 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4346. Merge change r1428167 and r1428560 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471598 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4346. Add a file missed in r1471598

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471602 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4243. Merge r1416709 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471603 13f79535-47bb-0310-9956-ffa450edef68
YARN-605. Fix failing unit test in TestNMWebServices when versionInfo has parantheses like when running on a git checkout. Contributed by Hitesh Shah.
svn merge --ignore-ancestry -c 1471608 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1471609 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/branch-2' into branch-2-gd
Merge remote branch 'origin/branch-2-gd' into fb-MAPREDUCE-4884-branch-2-gd