HDFS-7243. HDFS concat operation should not be allowed in Encryption Zone. (clamb via yliu)
YARN-2209. Replaced AM resync/shutdown command with corresponding exceptions and made related MR changes. Contributed by Jian He.

(cherry picked from commit 0f3b6900be1a3b2e4624f31f84656f4a32dadce9)

Conflicts:
	hadoop-yarn-project/CHANGES.txt