Twin headshell box

So here it is, a remix of the nice headshell case. The design was completely remodeled in Fusion360 so now I can do any changes on it quickly :) It's outer dimensions remain the same, inside I changed these:

- lowered the shell holders by 3.5mm
- shortened them by 2mm so it's easier to insert longer shells
- increased the distance between them by 1mm
- changed the retaining blocks in the upper lid, made them lower and a bit wider to follow the changes made on the shell holders
- the cut u