HBASE-8531 TestZooKeeper fails in trunk/0.95 builds

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1482669 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7006 [MTTR] Improve Region Server Recovery Time - Distributed Log Replay

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1482675 13f79535-47bb-0310-9956-ffa450edef68
HBASE-8547 Fix java.lang.RuntimeException: Cached an already cached block

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1482697 13f79535-47bb-0310-9956-ffa450edef68
HBASE-8547. Fix java.lang.RuntimeException: Cached an already cached block (Addendum to add better log)

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1482705 13f79535-47bb-0310-9956-ffa450edef68