[gta02-core] PCF50633 footprint and footprints in general

[Werner Almesberger]

I wrote:
> Hmm, I think I have to teach fped to "print" calculation results,
> so that we can check such percentages without using "bc".

Done. If you add something like

set pad_fill_perc = 100*nSPx*nSPy*SPx*SPy/(SLx*SLy)
set pad_area_perc = 100*SPxTot*SPyTot/(SLx*SLy)

and then click on one of the variables or their value, the percentage
will show in the status area. This also works for any other variable
value. (Except for loops at the moment, but they show the active value
in the frame list anyway.)

- Werner