How to request location service?

## 🚀 Feature Requests

I'd like to be able to check if the location service is activated, and if it isn't, prompt the user to activate it.

See also:
- [requestService()](https://pub.dev/documentation/location/latest/location/Location/requestService.html) function in [package:location](https://github.com/Lyokone/flutterlocation)

### Contextualize the feature

I'm using permission handler for all permission-related things in my app, but for this one thing (requesting the activation of location service), I have to depend on `package:location`. I'd this feature to be built-in into `permission_handler`.

### Platforms affected (mark all that apply)
- [x] :iphone: iOS
- [x] :robot: Android