Allow to use syncthing etc for sharing aircraft, routes, waypoints between devices

[baloan]

Is your feature request related to a problem? Please describe. I cannot find / do not have access to the location where EnrouteVFR saves its internal data. It may be in Android/data/com.akaflieg-freiburg.enroute but I don't see any files in there.

Describe the solution you'd like Please make the data directory for aircraft, routes, waypoints configurable so I can point my file synchonisation solution (syncthing or alike) to that directory.

Describe alternatives you've considered I managed to manually transfer routes by using Share...|GPX with a messaging app (Note to Self) and Import|Route on another device. This doesn't work for aircraft, though. And needless to say, it's not automated.