I3-compatible Adapto X-Carriage

Update: Extended the belt-holder part so that the belt won't budge down toawrds the x-carriage.

When building my new Adapto i wanted to use the MGS extruder instead of the wades-style extruder from the Adapto github repo so i made this.

This x-carriage has the same holes as the Prusa i3 x-carriage.

Things to improve:
Placement and style of zip-tie holes need to be changed to not interfere with the Prusa i3 extruder adaptor.

To mount the MGS-extruder, for now, you need to put washers or other spacers inbetween the extruder and X-carriage.