Bugfixing in the decorators containing mock data.

Separated out the decorators for the mock data in a new file.

Added initial mock data in the rest-client as decorators. Added was data from the database for a list and the possibility to use _http_request with PATCH or PUT.

Added the possibility to delete a list in the list info view. ...

Corrected small typos and added comments.

Added an error class to fieldset_forms to make sure fields not in the form raises an error.

Changed function names and calls in the view to make it work with the new rest-client. ...

Added the possibility to use fieldsets and divs in forms, by using as_div in the form.

Initial commit, added unsubscribe possibility to Florian's branch.