Add map rotation

[umonkey]

It is very inconvenient in the field to have to rotate yourself to understand the map. It would be very convenient to rotate the map itself and is unlikely to have this feature. Leaflet, unfortunately, is unable to do that. Reportedly Mapbox and OpenLayers are possible alternatives.

• https://docs.mapbox.com/mapbox-gl-js/example/navigation/
• https://openlayers.org/en/latest/examples/rotation.html

[umonkey]

MapBox GL can do that.

https://docs.mapbox.com/mapbox-gl-js/guides