Location Content for Review

Providers geolocation and map services for Sulu

__Tasks:__

- [x] test coverage
- [x] Add documentation
- [ ] gather feedback for my changes

__Informations:__

| Q             | A
| ------------- | ---
| Tests pass?   | Y (chez-moi)
| Fixed tickets | n/a
| BC Breaks     | n /a
| Doc           | Y
@dantleech ok than the structure is ok! but i think perhaps we need it for other things and than it should be public! but for the moment it is ok!