Ability to define fixed camera bounds to prevent the camera moving outside of an area

[malcolm-brown]

Currently there is no way to limit camera movement in such a way that it is prevented from moving outside a specified Latitude/Longitude bounds. There are ways around this (i.e. using OnCameraMoveListener or calling moveCamera every frame) but these often result in jumpy, stuttering camera movement.

Improvement is to allow an API method to specify a Latitude / Longitude bounds which the camera is unable to move outside of. This functionality has been used before in our C++ SDK and likely just needs wiring up to our APIs.