T-Bracket for T-slots

NOTE: This part has been superseded by a more customizable version: http://www.thingiverse.com/thing:1876275

This is similar to the OpenBeam T-connector here: http://www.thingiverse.com/thing:30524 -- this part has larger holes, designed for M5 screws, and the spacing between holes is large enough that you can use conventional T-slot mounting hardware. I've tested it with 20mm OpenBeam but I expect it to work with any T-slot system.

It's an OpenSCAD-based part, so it can be customized very