Z-axis Makerbot-style endstop holder for Prusa i3 variants

This is a remix of thing #64254 by Stefaan Ponnet. I simply changed the way the endstop is attached to fit Makerbot-style mechanical endstops. These endstops have the advantage of having an LED clearly showing the state of the switch which I find helpful when calibrating the Z-axis home position and leveling the heatbed.

The holder is clipped onto the Z-axis 8mm smooth rod on the motor side. This design can be used with just about any Prusa i3 variant, including the P3Steel as shown.

OpenS