Where-to-fly for Android version 1.5.0

Where-to-fly for Android, version 1.5.0, with the following changes:

• added support for live waypoints that update themselves periodically;
  supported are live waypoints to Garmin inReach and SPOT devices
• added support for where-to-fly:// URLs for adding live waypoints
• added long-tap menu entry "show flying range" to display a half transparent
  cone that shows the flying range, based on the glide ratio
• when adding a flying track, terrain height is sampled so that track is never
  "under ground"; non-flying tracks are clamped to terrain now
• added Sentinel-2 and OpenFlightMaps.org imagery layer
• added hiking tour planning support for some selected location waypoints in
  the Schliersee area.
• improved retrieving and caching of weather dashboard icons
• fixed opening .igc files from with negative latitudes or longitudes
• added Where-to-fly Windows app (beta)