Suggestion - API scheme improvement

[withsmilo]

Current Clipper provides the following clipper_admin APIs in Python level, but I think that some additional APIs will have to be implemented to maintain Clipper cluster.

• Add unlink_model_from_app, which unlinks specified model from specified application.
• Add unregister_versioned_models, which unregisters versioned models from Clipper Internal (remove all related resources as like working threads and queues also).
• Add unregister_application to keep consistency with others.
• Mark delete_application deprecated, but must be redirected to unregister_application.

[withsmilo]

All the APIs are implemented. Closed.