Add bearing to location tracking mode

[tobrun]

This ticket is a part of #2049 and focuses on bearing in user tracking.
This ticket follows after #2758 and #2712.

Discussed this with @ljbade and we came to the conclusion it would be better to divide bearing from tracking modes hence these can work separately from each other. For this I will add a BearingTracking.Mode class conform to MyLocationTracking.Mode.

[ljbade]

The idea is this:

With location tracking off, bearing mode will change how the user location marker arrow behaves.

With location tracking on, bearing mode will change how the map rotates.

[tobrun]

This ticket is almost complete, will wait to PR this until #2813 has been resolved.
Currently no able to do proper testing.