HBASE-9895: 0.96 Import utility can't import an exported file from 0.94

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1540927 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9918: MasterAddressTracker & ZKNamespaceManager ZK listeners are missed after master recovery

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1540934 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9917 Fix it so Default Connection Pool does not spin up max threads even when not needed

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1540946 13f79535-47bb-0310-9956-ffa450edef68