Bounding box restriction plugin

Capturing upstream from https://github.com/mapbox/mapbox-gl-native/issues/10302:
Currently, the Android Maps SDK has two options for restricting map panning: disable it completely, or don't allow the camera to move a single centerpoint out of view.It would be helpful to be able to restrict the camera to a bounding box as well.

We already expose a core based related feature but do not match the same behaviour as exposed on iOS. The plugin proposed here should cater the same user experience.

No repository files or tests are named. Start by reading the linked upstream issue and comparing the existing core-based restriction with the iOS behavior described here; done means the Android plugin provides equivalent bounding-box camera restriction behavior.

Written by the indexing model from the issue text.