This is the first step to allow the implementation of the registration form on the UI.
We need to offer a way to create a registrationdata token via API.
A registrationdata repository need to be created
- POST should get a json with the email address and return 202 (accepted as we want communicate the token via email for validation) if the email is valid and not yet in use by a registered user
- the other method GET (one, list), DELETE must be restricted to administrators