HBASE-9987 Remove some synchronisation points in HConnectionManager

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1543050 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9982 TestClientNoCluster should use random numbers

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1543052 13f79535-47bb-0310-9956-ffa450edef68