MAPREDUCE-6169. MergeQueue should release reference to the current item from key and value at the end of the iteration to save memory. (Zhihai Xu via kasha)

(cherry picked from commit 90194ca1cbd695d48c3705121c2ac9a8554578a2)
HDFS-7415. Move FSNameSystem.resolvePath() to FSDirectory. Contributed by Haohui Mai.
HDFS-7415. Addendum patch to update CHANGES.txt for HDFS-7415.
YARN-2375. Allow enabling/disabling timeline server per framework. (Mit Desai via jeagles)

(cherry picked from commit c298a9a845f89317eb9efad332e6657c56736a4d)