Higher version of all in one case

This is my remix of Michael's 'TeachingTech' case. I also used jameswoodward's remix as input.

What I changed:
* raised the hight of both boxes by 12 mm as I use the rubber feet (https://www.thingiverse.com/thing:3020865) for my ender and so have more room under the printer.

MKS box:
* reduced the size of the hole for the USB plug
* closed the SD card slot
* added more air slots
* added a holder in the MKS box for a 40 mm fan

MKS box lid:
* added an additional slot for cables and