Revised Interchangable Mouse Ears

I found [these great mouse ears](https://www.thingiverse.com/thing:3687547), but the mesh was not of great quality, which makes it hard to easily edit or slice. Thus, I imported the mesh into FreeCAD and reverse-engineered it into a parametric model. Modify it as you please.

Attribution to Original:
Star Ears byhackersis licensed under the Creative Commons - Attribution - Non-Commercial license.
See original [here](https://www.thingiverse.com/thing:3687547)

Updated 4/8/2022: Fixed a magnet hole that was too small. I had forgotten to set any diameter at all.