Facilitate API/UI integration by providing API stub

This change adds the new user-API to update/create users in ChornoZoom by sending a PUT request to: http://server/chronozoom.svc/user with a user object.

Triggering this operation creates a supercollection/collection for this user and the API returns back an URL to the created collection.

Database changes are currently pending and will be implemented after this check-in. Therefore, user information won't be persisted (email for instance).

Code Collaborator: http://mrccodereview.cloudapp.net/ui#review:id=1098
UW Approved. Missign MSU approval.