TUSH Lite

I remixed The Ultimate Spool Holder to:
- Fit four bearings i had laying around which were differently sized
- Use way less plastic
- You can now fit a M6 threaded rod to space them correctly, make the structure sturdier and you can also apply a little convergence so that the spool doesn't roll off
- There is a version of the spool holder which uses two small tabs that prevent the spool from rolling off.

I will post the .f3d later so it's even more customizable