YARN-677. Increase coverage to FairScheduler (Vadim Bondarev and Dennis Y via jeagles)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1528528 13f79535-47bb-0310-9956-ffa450edef68
Merge -c 1528533 from trunk to branch-2 to fix MAPREDUCE-5530. Fix compat with hadoop-1 in mapred.lib.CombinFileInputFormat by re-introducing isSplittable(FileSystem, Path) api and ensuring semantic compatibility. Contributed by Robert Kanter.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1528535 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1528620 FIXES: HADOOP-9254. Cover packages org.apache.hadoop.util.bloom, org.apache.hadoop.util.hash. Contributed by Vadim Bondarev 


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1528621 13f79535-47bb-0310-9956-ffa450edef68
Merge -c 1528626 from trunk to branch-2 to fix MAPREDUCE-5459. Update documentation on how to run MRv1 examples on YARN. Contributed by Zhijie Shen.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1528627 13f79535-47bb-0310-9956-ffa450edef68