Arduino DIN case

I needed a DIN case that would fit an Arduino UNO, LCD, Arduino shield and a Solid state relay. So I took this https://www.thingiverse.com/thing:3402441 one and altered it a bit.

Things changed:

- Moved Arduino to right to make room for shield
- Made it bigger (7 units)
- Removed fan
- Added mounting for Solid state relay
- Moved cable in
- Other small improvements