Readthedocs needs checking

[Davidy22]

The docs badge has been marked as failing for a while. Recently we got a patch that cleaned up some moans from the docs build, which didn't change the build status for docs. I also noticed that a recent addition of installation instructions on manjaro isn't actually appearing on readthedocs.

https://guake.readthedocs.io/en/latest/index.html

Whoever has access to the readthedocs account, is it pointing to this repo? The last commit that readthedocs seems to have picked up from the repo was from two years ago. I think readthedocs has error messages, can whoever it is who has the account bring out the error messages, fix them if it's an account config deal? Paging @gsemet because they might know who it is.

On the topic of neglected badges, the bountysource badge seems to have been broken by an API change at some point.