Feature/chargecard selection

[Thorsten1]

This will add an option to the settings, where the user can select the charge cards he/she likes to be visible.

Discussion: Maybe we should invert the behaviour, so users can check the providers they want to hide. This way, newly added charge cards won't be automatically hidden. On the other hand, I guess people who hide ChargeCards aren't interested in new ones anyway

TODO:

• [x] Add a more complete default List of available ChargeCard Providers
• [ ] Add an automated retrieval of supported Providers via an API endpoint

[macschlingel]

@Thorsten1 kannst du das mal auf den Master rebasen bitte?

[Thorsten1]

@macschlingel Wollen wir das noch reinnehmen?