make minimal sides thicker

[jaredjennings]

The thing that gave this fork of the Dactyl its name was the marshmallowy sides. At this moment I'm not even trying to make them. But the bare web I'm printing out, with the key holes in it, is too thin at the corners and edges. It cracks apart when you put a keyswitch in it. So the edges and corners of the web need to be wider, irrespective of the marshmallowy sides.