Bowden Clamp with Zipties for Rostock

This is a beefier version of the bowden clamp for rostock. I decided to use 3mm filament so the original version was a little bit too small. Then I didn't have a proper nut to hold the tube in place like the original, so I decided to add grooves to the jaw so I could use zipties.

I hold my hotend in place with long screws on each side of it, so I also changed the body to have a square center part instead of a rounded one.

I also added a parameter to this clamp in the scad file, so it can b