Code that could be included:
* http://github.com/l0b0/qr2scad
* http://github.com/l0b0/img2scad
* http://github.com/l0b0/OpenSCAD-Minimizer
* http://www.thingiverse.com/thing:4656

Integrate these better:
* bitmap

Testing:
* add tests for openscad functions