Add a note indicating the PCB thickness and color.
Also, move the drill origin to the lower-left corner, to aid in machine
assembly.
Signed-off-by: Sean Cross <sean@xobs.io>
Add more silk, indicating website and other info.
While we're at it, move some traces around to give more copper area, and
drop some more vias to improve ground performance.
Signed-off-by: Sean Cross <sean@xobs.io>