GSO Monorail 1:10 focuser

This is a motor focuser for a GSO Monorail focuser with 1:10 fine focus.
It uses the code from https://github.com/fehlfarbe/arduino-motorfocus

bom:
- 4x M3x20mm DIN912 for mounting to the focuser
- 2x M3x10mm DIN912 and 2x M3 locknuts for mounting the stepper motor
- 1x stepper motor + board (5V 28BYJ-48 with ULN2003 driver board)
- 5V Arduino nano clone (ATmega328P CH340 chip)
- 6x female-female 200mm jumper cables

The Arduino Pins D3-6 connect to the IN4-1 on the driver board. GND