[Authorization] ServiceAuthorizationManager isn't dynamically updatable. And it should be.

Some more background information.

ServiceAuthorizationManager is responsible for the Services access rights defined in hbase-policy.xml which locates under $hbase_home/conf directory.

Currently, since it doesn't support update dynamically, we need to restart master/regionservers to make configurations take effect. It is an expensive and low efficient admin operation.

HDFS has the refreshPolicy to do that, HBase also has update_config command, we can make use of that.