MK3s Hemera upgrade

It is a modified version of MK3s to hemera upgrade based on the following:

https://www.thingiverse.com/thing:4058436
https://www.thingiverse.com/thing:4031637

In addition it allows to use filament sensor with it but for now it is experimental work. The idea is to use two 9mm magnets to keep the lever sturdy pressing against the extruder lever. Hemera lever is moving always by this same distance despite the knob setting.

PINDA probe was relocated to keep x axis similar to original mk3s. You will need to make changes in the firmware as per e3d tutorial with following changes from the original:

1. Change LANG_MODE to 0
2. Change #define X_PROBE_OFFSET_FROM_EXTRUDER 23 to 26
3. Change Y_PROBE_OFFSET_FROM_EXTRUDER 5 to -33.8

https://e3d-online.dozuki.com/Guide/Prusa+i3+MK3+Firmware+Modifications/141?lang=en


XYZ calibration will not work after this upgrade so you will have to use mesh bed leveling and first layer calibration to start printing.

Added .step files f