rubber ball feet (45mm) for 2020

I really liked gobo38's squash feet for 2020 etrusion design but the cheap rubbber balls I purchased did not fit so I created new ones in Tinkercad based on gobo38's design.

### Hardware Required
* 2x M3 screws (per foot)
* 2x M3 T-Nuts (per foot)

### Tinkercad
Feel free to tinker as much as you like :)
https://www.tinkercad.com/things/jDshqb6fMXk