Feature to exchange the backend save format to yaml

[nraw]

I believe using yaml instead of json to store the .tdda files would make editing checks manually easier

[njr0]

Thanks for this suggestion. I must admit, while YAML is clearly less annoying to write, I'm not keen on it as, in my experience, it's rather brittle, ambiguous, idiosyncratic and non-portable. That doesn't seem ideal for a library focused on improving quality. StrictYAML might be a better fit. Have you had any experience with that?