runway: Move getprop() call to get_short_runway_distance() function
runway: Move make_notification_cb() to runway.make_betty_cb()
runway: Fix remaining-distance during RTO when not leaving runway
runway: Use a single property to decide whether aircraft is on ground
runway: Require groundspeed < groundspeed_max_kt for approaching-runway
runway: Support approaching-(short-)runway when aircraft is airborne
Merge pull request #3 from onox/master

Add approaching-(short-)runway when aircraft is airborne