Orange PI PC slimline clip case

This case is designed to be laser cut from 3mm acrylic. The case is
for the Orange PI PC (not plus or opi2).

This design has a top that can be easily flipped open to get access
and is several mm shorter than previous designs. The top cover being
level with the top of the USB connectors.

The tolerances are very close but the design has been successfully
realised, though even the protective plastic covering upsets the slot
sizes enough to cause issues.

Using 1/8th inch acrylic does n