HBASE-11737 Document callQueue improvements from HBASE-11355 and HBASE-11724 (Misty Stanley-Jones)
HBASE-11736 Document SKIP_FLUSH snapshot option (Misty Stanley-Jones)
HBASE-11553 Abstract visibility label related services into an interface.
HBASE-11744 RpcServer code should not use a collection from netty internal
HBASE-4955