HBASE-12666 TestAssignmentManager hanging; add timeouts
HBASE-12493 Make User and TokenUtil public

Conflicts:
	hbase-common/src/main/java/org/apache/hadoop/hbase/security/User.java
	hbase-server/src/main/java/org/apache/hadoop/hbase/mapred/TableMapReduceUtil.java
	hbase-server/src/main/java/org/apache/hadoop/hbase/mapreduce/TableMapReduceUtil.java
	hbase-server/src/main/java/org/apache/hadoop/hbase/security/token/TokenUtil.java
	hbase-server/src/test/java/org/apache/hadoop/hbase/security/token/TestTokenAuthentication.java
HBASE-12348 preModifyColumn and preDeleteColumn in AC denies user to perform its operation though it has required rights

Signed-off-by: Andrew Purtell <apurtell@apache.org>
HBASE-12686 Failures in split before PONR not clearing the daughter regions from regions in transition during rollback (Vandana Ayyalasomayajula)