Case for mp3 decoder board HW-188-JL

#Case for cheap mp3 decoder boards.

(some of the boards are labeled "HW-188-JL", mine is)

##Update: In v1, the hole for the audio plug is 9 mm; v2 is 10 mm (not yet printed

Also the v2 lid is changed to have a smaller key area so the hole is still printable (it would not be, otherwise).

##Files I printed successfully:

flat top keys.stl
normal right wall base.stl
normal right wall flat top.stl (turned 180° in the slicer)

I printed the case using a big nozzle and large layer he