Opening Cage Miniature (S3D Fix + Variations)

Remodeled from DungeonLester ([link](https://www.thingiverse.com/thing:2850581)), which I really liked, but the original didn't play nice with Simplify3D. I build a new version from scratch in Fusion360, exactly copying the original, but making sure that the parts are completely solid. This version will slice correctly in Simplify3D.

Furthermore, I've added 2 wider variations, one with the door on the front, and one with the door on the side. Other sizes are available on request.

All credi