WIP Possibility to delete account

:construction: Work In Progress, don't hit merge yet.

Added a

TODOs left: 
- [x] Make it work
- [ ] Add one test
- [ ] Add other test
- [x] Make it presentable
- [ ] After deleting a account (of two) there appears a error msg 

@Gomez as discussed - there is no need for the settings controller - the accounts controller can be used for returning the accounts. THX