Data layer support

## Feature Request

### Plugin
@capacitor/google-maps

### Description
Google maps has a data layer feature, where it is possible to i.e. add a geoJson data object. They call it 'map feature'.
https://developers.google.com/maps/documentation/javascript/datalayer

### Platform(s)
Android
iOS
Web

### Preferred Solution
The following methods could be implemented in the first implementation:
- a method to add features
- a method to remove a feature
- a method to get the bounds of a feature