gEDA-dev: footprint cleanup

[DJ Delorie]

> I wish for more per-part attributes in the PCB
> database.  Right now it has:

I was thinking of adding a generic attribute feature
to elements:

Element[ . . . ] (
   Attr("name" "value")
   Attr("name" "value")
   Attr("name" "value")
)

This would let us put author and copyright info in, even if we can't
do anything with it inside pcb itself.  PCB just has to preserve them
for now.