docs: consistency changes

[BBosman]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request? (put an "X" next to an item)

[X] Documentation update
[ ] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[ ] Add autofix to a rule
[ ] Add a CLI option
[ ] Add something to the core
[X] Other, please explain:

What changes did you make? (Give an overview)

I've made a bunch of consistency changes to the rules documentation, including:

• Fixed header casing (i.e. options -> Options)
• Fixed header levels (i.e. ## allow -> ### allow)
• Removed duplicate headers (i.e. multiple ## Rule Details headers)
• Made all inter-rule links internal links if they weren't already (i.e. [object-shorthand](https://eslint.org/docs/rules/object-shorthand) -> [object-shorthand](object-shorthand.md))
• Made unordered list style consistent (i.e. - -> * ). Almost everywhere * was already used so fixed the few places it wasn't. I also added an entry to markdownlint.yml to ensure future consistency. This also resulted in a couple of changes outside of the rules directory.
• Made the order of sections consistent. The order is now always "Rule Details", "Options", "Environments", "Examples", "Known Limitations", "When Not To Use It", "Related Rules", "Compatibility", "Further Reading". Especially those last three had quite a few permutations. The order is arbitrary, but made sense to me.
• Added a test to Makefile.js to validate those header names and their order
• Some typo fixes and similar minor changes.

Is there anything you'd like reviewers to focus on?

This is my first PR to eslint and I think I followed all guidelines, but I'm happy to make improvements to the PR if needed.

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Bas Bosman (925d3b6)

[aladdin-add]

LGTM, just a minor suggestion.

[aladdin-add]

LGTM, thanks!

[nzakas]

Thanks, this is some nice work. Just a handful of changes I don’t think we can make but overall looks good.

[BBosman]

@nzakas, I think I addressed all your comments.

[mdjermanovic]

Very nice work, thanks! I left only two small suggestions.

[mdjermanovic]

LGTM, thanks!

[snitin315]

Nice enhancement. Thank you for your contribution.