- Waypoints: Until now stat_id was saved but never assigned to. Instead we now save the GRFID/local index of the custom graphics so that GRF file changes can leave graphics intact.
- Check if the vehicle exists
- Check if the vehicle belongs to the correct player
- Check if the new order is valid (type, destination, flags) (CmdInsertOrder)
-Codechange: rewrote some functions while moving waypoint-stuff
-Add: added support for 64k waypoints
-Fix: made the waypoint struct a bit more logic (no bit-fucking)