Port of CWS-Umbraco-Standard-Membership to the new U7 Membership APIs

The original code was written by Warren Buckley:

https://github.com/warrenbuckley/CWS-Umbraco-Standard-Membership

and

https://github.com/warrenbuckley/CWS-Start

Most of the code is extracted from the latter project as I found the former to be only partially functional.

All code interacting with members was upgraded to the U7 MemberService and SurfaceController.Member.