Refactor as Ansible Collection and Roles

[db0]

As requested here: #180

I am delivering a proof-of-concept refactor on how you can switch the current repository to ansible collections and roles. For this initial draft, I have simply split the lemmy stuff from pictrs-safety into individual roles and added the 'photon' role. The expectation is that each component of lemmy can be split into its own role. backend, rust_ui, pict_rs, pictrs_safety, proton, alexandrite etc

The backend role contains every lemmy component right now, as I don't have time to do more. But the way I extricated pictrs_safety can be used for the others, and to add new frontends follow the approach of photon. I don't know the process to make a frontend the "default", so you'd have to add that yourselves.

I have also made some improvements on your existing ansible code:

• Avoid creating new playbook per distro. One role can handle multiple distros, by using include_tasks and lookup and only the distinct code per distro needs to be split.
• Switch to using inventory.yml instead of hosts for better readability

Note: This collection is untested. There's may be some syntax errors etc. But the general conversion is accurate..

[codyro]

You stated in the parent issue that you're done working on this at this time. If that's the case, would you mind if I fork this and make some (opinionated) tweaks?

[db0]

Feel free to fork it, or work directly on my branch. Yes I'm done working on it for now due to other commitments.

[ticoombs]

Closing. Thanks for the PR example!