gEDA: pcb - indicating slots/cutouts

[Ales Hvezda <ahvezda-at-NOSPAMseul_dot_org>]

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-- Cut here -- 
From: Alexander Perry <alex.perry@qm.com>

Is there a correct way to draw a slot (i.e. something that needs to be 
cut with the router rather than the drill) in pcb such that the gerbers
don't do something odd ?  I'm quite happy to make a note in top silk,
pointing out which piece of FR4 should be removed for the human to see.
I just don't want any surprises when machines read my gerber set.