Enclosure for OpenVizsla USB Sniffer

Basic enclosure for the OpenVizsla.

Dimensions taken (sloppily) with calipers rather than going from the design files, so aren't spot on, but it's still not a bad box and will help give some protection.

Tested in ABS; I wouldn't expect any problems in PLA. Made to use 4 x ~3mm self-tapping screws -- the ones I'm using came from flotsam in a random drawer, so YMMV.