Anycubic Chiron hotend housing V3 / Hotend Gehäuse v3

in eglish:
This is a remix based on [Chiron hotend housing for silent fan and optimised cablechain](https://www.thingiverse.com/thing:3326593) from [bmwoholic](https://www.thingiverse.com/bmwoholic).

Improvements:
- additional mount at the lower right side (uses the original thread)
- counter-nuts M3 for the fan duct
- fan duct mount is situated a bit higher to avois collisions
- fan duct is 6mm nearer to the nozzle
- place for a small LED including switch
- cable mount after the cab