add web-thickness configuration for manuform

[happysalada]

this adds the ability to define web-thickness (thickness of the top part of the keyboard, around the holes)

[happysalada]

There are lots of line change, but it is a fairly straightforward change. Let me know if anything.

[happysalada]

I only did the manuform part and left the lightcycle part as is. The change for the lightcycle part should be pretty straightforward.

[ibnuda]

thanks.