YARN-2189. [YARN-1492] Admin service for cache manager. (Chris Trezzo via kasha)
(cherry picked from commit 78968155d7f87f2147faf96c5eef9c23dba38db8)

Conflicts:
	hadoop-yarn-project/hadoop-yarn/bin/yarn
HDFS-7454. Reduce memory footprint for AclEntries in NameNode. Contributed by Vinayakumar B.