gEDA-dev: [pcb] physical layer stack

[DJ Delorie]

> Why do you think you will need to go multiline?

Pin, for example.  For each layer, you have a different shape/size
pad, plus the GUI could have extra flags for colors or selection
status.  Add to that shapes for solder mask on each side, etc.

For solder pads we have pad shape, mask shape, extra mask (for
paddles), paste shape(s), etc.

Plus there's options for third-party attributes, etc.  It won't all
fit on one line *and* be extensible.