HBASE-11474 [Thrift2] support authentication/impersonation
HBASE-11493 Autorestart option is not working because of stale znode 'shutdown'(Nijel)
HBASE-11497 Expose RpcScheduling implementations as LimitedPrivate interfaces (Jesse Yates)
HBASE-11039 [VisibilityController] Integration test for labeled data set
mixing and filtered excise (Ram)
Merge remote-tracking branch 'remotes/origin/0.98' into 0.98