[WIP] Arch support (POC for multi-distro)

I started pulling the OS-specific tasks apart to support multiple Distros in the future. For now, i focused on Archlinux just to get started.

I mostly replaced specialized tasks with ones, that are readily available in ansible (or in docker's case ansible galaxy - let me know what you think about that!) and added a layer of abstraction when installing packages.

Current status

• HLOS is deployable to Archlinux with no changes in config
• Traefik is running
• i probably broke other things

I will put this on hold until some changes have been made upstream, so this MR can be smaller.

Help appreciated

This is by no means finished and I'm hoping for input from more experienced ansible users. I left some TODO's where I'm still unhappy with the result and could use some help.

It would be great if some of you could chime in for a healthy discussion.