HAL 9000 (v3)

V4 is now online: https://www.thingiverse.com/thing:5365345
This is an update to v2 of my HAL 9000: https://www.thingiverse.com/thing:4848847

Major changes:

- Raspberry Pi Zero 2 (instead of Pi 3 or 4); now enough space to also mount FT232h and for better cable management
- software: migrated from [mycroft](https://mycroft.ai/) to [kalliope](https://kalliope-project.github.io/) for much improved performance and voice recognition (at the cost of manual configuration of each skill/task) -> [basic setup repo on github](https://github.com/juergenpabel/HAL9000-kalliope)

Minor changes:
- top opening now bigger and optionally with cover for easier access and easier power cable routing options
- Speaker grill (bottom) with square (instead of round) holes for better printability
- removed internal pin holes for connecting bottom and top halves (use turnbuckles)
- removed screw holes for wall mounting;