HBASE-12401 Add some timestamp signposts in IntegrationTestMTTR
Replication gets stuck following a transient zookeeper error to remote peer cluster

Conflicts:
	hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSinkManager.java

Signed-off-by: Andrew Purtell <apurtell@apache.org>