Label Dispenser

This is for the Ultimaker challenge. FWIW, challenge wise, I'm a maintainer of MCAD and a meta-maintainer of github.com/SolidCode. I'm also THE RepRap/RepLab evangelist here in Finland ;)

Anyway, on to interesting stuff:
I've refactored the code, making the parametrization better, and added a roll holder so that a label roll can sit inside the dispenser. Currently the size of the roll is limited somewhat, I intend to refactor some more to make allowances for bigger rolls. Support for packing tape might come too. A handle is planned, and I have some vague ideas to mechanize it, in the spirit of packing tape dipensers. If anyone can link pics of the inner workings of one, it would be useful ;)

Update: Added a guard that should keep the roll in. Handle might be coming next...

Update2: Refactored the code so that now it can be adapted for bigger rolls automatically, see image. I'm mostly pleased with the code now.

Update3: Added a handle!

Update4: Added holes for some prope