Generate an all-rules.csv file

[WilcoFiers]

While we do have our rule-descriptions.md, it comes up somewhat regularly that organisations want to use rule information for developing internal documentation. The rule-description file is a little short on details in that, and having a CSV file will make it easier for people to filter things as needed.

The CSV should have columns for different types of tags. One category column, a WCAG level / best practice column, a WCAG criteria column. It should also include the rule help text, not just the description. Whether that's an EN rule, an 508 rule, an ACT rule. And for WCAG tags it would be useful to include the success criteria text, and a link to the understanding document.

[WilcoFiers]

Closing, as we have an alternative proposal to address the question outside of axe-core.