Arduino M0 Pro Zero Case

This is almost entirely the work of Zygmunt Wojcik who has designed some excellent Arduino cases. See his work for more details on printing and assembly: https://www.thingiverse.com/thing:628929

I've modified his OpenSCAD files with the second USB connector and moved the LED and Reset cut-outs, so it can be used as an Arduino M0 Pro case. May be suitable for Zero