Force Editor units to be in editor_only continent

[MiamiCenterPL]

I really wish for the editor to show me atleast a warning like 'You're placing unit that is supposed to be Editor Only, would you like to switch continent?' when attempt spawning a nav_splitter in the world continent.
Obviously an option to make editor spawn these kind of units only in editor_only continent would really help :)
There goes every nav splitter, blocker, ai covers and probably I forgot about tones of others :v