Cube callibration test (added highres and 1cm versions)

This allows you to quickly callibrate your new 3d printer be it reprap, printrbot or whatnot. It's a 2cm cube with a 1cm hole along the x-ax.

Just added a highres version so the hole is more circular and it's centered.
Also added the openscad file for this and a 1cm version with 5mm hole for printing at 0.1 layers this one is a good test...

The original file is a smaller download so kept it...