[FR] Turn Angle to Next Waypoint

[JNavas2]

When sailing, the Turn Angle to the Next Waypoint would be very useful.
If a boat has a tacking (or jibing) angle of (say) 80 degrees,
when the Trun Angle gets to 80 degrees, then it's time to tack or jibe.
Note that there are 2 different ways to calculate Turn Angle, Bearing to Waypoint versus:

1. COG (GPS)
2. Heading (compass)

There can be a difference between the two when there is current.
Since different users may prefer different calculations, it would be ideal to have both.

Our use case is internal GPS in an Android tablet with waypoints stored in the app, but others may need NMEA.

Thank you!