Make last release's docs the one that users land on

[alexdewar]

At present, we send users to the development version of the docs, which is possibly not what we want, as it may be unfinished, include references to in-development features etc. It might be better to send them to the page for the last release instead.

Marking this as "on hold" because I think we should discuss first.

It probably makes sense to do #1193 before this, too.

[AdrianDAlessandro]

Began working on #1193 and found that it only makes sense to tackle this at the same time