HBASE-9467 write can be totally blocked temporarily by a write-heavy region

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523881 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9510 Namespace operations should throw clean exceptions

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523902 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9510 Namespace operations should throw clean exceptions

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523903 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9555 Reset loadbalancer back to StochasticLoadBalancer

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523914 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9555 Reset loadbalancer back to StochasticLoadBalancer; ADDENDUM

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523926 13f79535-47bb-0310-9956-ffa450edef68
Small fix for build tool

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1523945 13f79535-47bb-0310-9956-ffa450edef68