Prusa MK3 Mean Well LRS-350 Specific Mount

This is a remix of https://www.thingiverse.com/thing:2812350 (Mean Well LRS-350 version) with a few small modifications:

* The entire mount is shifted one millimeter in the positive X direction (based on a source comment)
* The vent side wall was lowered to expose another row of vent holes.
* A hole on the back side was added to expose a couple more vent holes.
* Some fillets, just because :)

[Edit 07/21/2019] Added Fusion 360 file