Update docs and remove scenarios.yaml

[brynpickering]

Fixes #230 & #236. Reverts #209.

Since we are now modular, it's impossible to have any one file that links to the contents of multiple other files (as scenarios.yaml was doing in grouping overrides). So, we have to remove this file and instead document how one would create their own scenarios by grouping overrides.

Checklist

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• CHANGELOG updated
• Minimal workflow tests pass
• Tests added to cover contribution
• Documentation updated
• Configuration schema updated

[timtroendle]

@brynpickering is this ready to be reviewed again?

[brynpickering]

Yes!

[timtroendle]

I like it now!

One small thing needs to be fixed: all code boxes (yaml and python) in the overrides section of customisation.md are broken (have a look at the readthedocs preview). Not sure what's going on but it's basically unreadable right now.

[brynpickering]

Hmm, the code blocks render just fine when I build it locally:

[timtroendle]

It works for me too. Also, I figured just now, that these code blocks are broken in other parts of the documentation on readthedocs, too. That's weird. Is it possible that this is a glitch in the built?

[brynpickering]

I checked the supposed dead markdown link (https://open-power-system-data.org/) and it isn't dead.

[timtroendle]

Thanks a lot for following up on this, @brynpickering . It all looks good to me now, apart from the erratic behaviour of the Markdown link check. We need to investigate what's going on or otherwise remove it. It's suspicious that it's consistently open-power-system-data that's failing.