feat: allow antimeridian span for LatLngBounds and CameraFit

[JetA2]

This addition allows a CameraFit spanning the antimeridian to be created using CameraFit.boundsor CameraFit.insideBounds. It was also necessary to add a new constructor LatLngBounds.unconstrainedLng to be able to create bounds that span the antimeridian.

Example: showing the airports at Magadan and Anchorage on a map.

Before (using CameraFit.bounds with LatLngBounds.worldSafe):

After (using CameraFit.bounds with LatLngBounds.unconstrainedLng):

[JaffaKetchup]

Hey, thanks for this. We're actually looking into better anti-meridian and direction wrapping control of latlngs at the moment, so I'm not going to merge this just yet in case we change things with LatLngBounds. But at the moment, this is great!