HBASE-7684 NullPointerException in SecureClient when Call is cleaned up due to RPC timeout (cuijianwei)

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1440282 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7705 Make the method getCurrentPoolSize of HTablePool public (cuijianwei)

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1440283 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7685 Closing socket connection can't be removed from SecureClient (cuijianwei)

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1440285 13f79535-47bb-0310-9956-ffa450edef68