Tootfinder

So, spent most of the day getting Handbrake compiled with the `svt-av1-psyex` and `svt-av1-essential` forks of the SvtAv1 encoder. However, I did win that battle and both are now available in the `sisyphus-client` containers. Definitely a pain in the ass, but it's nice to have options depending on what you want to use. Also updated the documentation to make sure I don't forget which is which.
I still need to implement some pipelines to build these, but holy crap the Handbrak…