YARN-447. Move ApplicationComparator in CapacityScheduler to use comparator in ApplicationId. Contributed by Nemon Lou.
svn merge --ignore-ancestry -c 1463405 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1463406 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/branch-2' into branch-2-gd
Merge remote branch 'origin/branch-2-gd' into fb-HADOOP-7435-branch-2-gd