Quaden Hat and Insert Remix

This remix of Sindarius excellent Bowden upgrade for the M3D Crane Quad print head with the following changes:

1. The geometry of the Quad Bowden Hat has been reconfigured to allow printing without any supports.

2. I moved the Inserts that fill the holes where the motors would normally be mounted to the inside of of the Quad clamshell. This design eliminates the need to use the original bearings. The inserts also have allen key / flat head screw fittings to allow for rotation once the cla