DocumentHandle workflow must not extend deprecated ReviewedActions and UnlockWorkflow

We deprecated the ReviewedActions workflows and friends (Unlock, Request, etc.) but currently the new DocumentWorkflow extends some of these.
This is undesirable because it leaves the opportunity that developers will (still) cast or expect a DocumentWorkflow instance to implement (also) these deprecated workflows.

I'll short-circuit this undesirable effect by inlining the 'inherited' methods of these deprecated workflows instead of extending them.