Oral-B electric toothbrush head cover

Small remix the Oral-B head cover from tilmansp.
https://www.thingiverse.com/thing:2011432

I added more venting to the cap and made the clip a little stronger.
Also removed some material to make it look sleeker.

As a consequence we get now a lot of overhang, so enabling support is a must (still look far from perfect on my sample).
As of the stronger clip I would recommend PETG over PLA. PLA might be to stiff an crack.
With PETG it hold now very strongly on the head.