[4xiDraw] Arduino Grip Snapon

I had to print a GT2 pulley. As the pulley was bulky I couldn't fit the original Arduino grip after installing the pulley so I modified the grip and made it snap-on.

Fits nicley and tight on the smooth rods.

##### Update 27. August 2016
Added: Arduino grip_snapon_v2.stl
- Raised the height of the part so the stepper motors axis does not grind through the PCB doing fun sparks and blue magic smoke.
- Made the snapon more tight to be more fixed. Harder. Better. Faster. Stronger.