HBASE-10513 Provide user documentation for region replicas

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/hbase-10070@1595077 13f79535-47bb-0310-9956-ffa450edef68
HBASE-10810 LoadTestTool should share the connection and connection pool

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/hbase-10070@1595078 13f79535-47bb-0310-9956-ffa450edef68