It would help if LuaATC tracks and operation panels could send ATC
commands to trains, which are not on a LuaATC track.
The trains have an unique ID, so identifing should be no problem.
To prevent trouble the command should only be legal, if
-the train (any owner) is on tracks in an area with the same owner as
the area of the LuaATC track/operation panel
- the train (same owner *) is in unprotected area and not under control
of interlocking from another player
same owner: it should be possible that one player allows other
player(s) to control his/her trains remotely (eg: freight trains from
several players and operated by one player)