HTTP API

Client:
- Added JSON Template class for registration messages
- Added doRegister Method, which now creates a new user account on the backend.
- Cleaned up some JSON templates

Server:
- Setup notizync Database
- Added implementation for registering&logging in

PC GUI
- Added Controller class for User registration
- Fixed a Bug with the settings saving userdata, even tho the checkbox wasn't checked
- Updated Model
  - Added doLogin, doRegister Methods which will now forward to the HTTP API
  - Added HTTP API as RemoteStorage

As of today, only the Synchronisation Implementation itself, registration/login should now work properly.