SDR RSP1 Case

I made the following changes:

- Relocated the holes for the SMA connectors to align with the board.
- Aligned the screw holes for the SMA Header with the case.
- Aligned the screw holes for the cover with the case.
- Added a slot to mount the board in. This keeps the board from floating around
in the case and does not require any hardware to hold the board.
- Resized the SMA Header height to match the height of the case and cover.

I used PRUSA Slicer to add paint-on supports on the case for the SMA header and the USB openings. Print time for all three pieces was 2h 37m using a .4 nozzle and .0.25 layer height.