i3 X Endstop Mount for Sainsmart endstops

Just a quick endstop holder for the Prusa i3 X axis that will hold Sainsmart and probably other endstop boards.
Note: for M8 45mm center i3 X axis which are pretty standard.

**Check out AndrewBCN's Prusa i3 / P3Steel Improved Endstop Holders Collection http://www.thingiverse.com/thing:612028/#comments remix for a slightly stronger version.**