Created by: nero
Goal of this PR:
- Move similar code together. Currently, networking & blockdev setup are spread out over several places.
- Create marked and documented sections or functions with specific purposes (e.g. "make blockdevs available", "network device and configuration", "setting up live rootfs") so code contributors have better orientation where to add code for features.
- Improve comments by explaining the why behind certain code
This is not intended to create significant functional differences.