docs: Normalize links to https or their web archived version when unavailable

[echoix]

I had worked on last February to change http links to https when possible. Down that rabbit hole, I opened every link I saw to see if it had a https version, and when the link was dead, I made a separate research to find where that content is found now. When it was impossible to find an equivalent content hosted somewhere, I changed the link to a link to the wayback machine. Since I used the Internet Archive extension at that time, I also made sure that every link I opened was at least backed up in the last 90 days, as of February 2024. I also used the wayback machine to help find the location of a moved website that didn't have redirects anymore.

I was extensively using search and replace, and also normalized multiple different URLs from different files to be uniformized across the repo, when it made sense. Example: taking permalinks when available, using the recommended URL scheme for publication ids, DOI, etc.

I had an open PR in my fork of this work where I asked for some feedback before posting here.

I'm opening the PR right away, but I'm currently rebasing the commits to remove already committed fixes (to enable linting), and some URLs recently independently updated.

[neteler]

With the few suggested modifications applied good to go.