Modified Case for SQFMI's Beepy

This is a simple modification of a8ksh4's “slim_flat” Beepy case, which adds openings on the back to help improve airflow around the Raspberry Pi and closes off the power-only micro USB port so you don't accidentally connect anything to it. The front is unchanged.

Two rear files are provided, one with the SD card slot and one without. Either one will work, as they are otherwise identical.