- Add flightgear_bridge submodule. - Add traget px4_sitl_nolockstep with disabled LOCKSTEP simulation. - Add flightgear viewer targets and startup scripts - Add a few possible vehicles plane (rascal), autogyro (tf-g1), and rover (tf-r1)) Co-authored-by: Vit Hanousek <vithanousek@seznam.cz>