Markdown Linter

[aokellermann]

Changes

• Adds markdown linter
• Enforces 120 characters line width
• Related to Linter #247
• Closes Line length limit for Markdown #582

Examples

Some common errors:

---

This change is 

[maxitg]

Reviewed 18 of 18 files at r1.
Reviewable status: all files reviewed, 5 unresolved discussions (waiting on @aokellermann)

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.markdownlint.json, line 7 at r1 (raw file):

  "no-blanks-blockquote": false,
  "no-duplicate-heading": false
}

Add an empty line at the end of the file.

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.github/CONTRIBUTING.md, line 27 at r1 (raw file):

3. Fill in all the fields including:

  * Brief description in natural language.

This should actually be indented by an extra space (without empty lines before and after). Then, it is correctly displayed as a sublist of (3), and the lint errors disappear without the need to disable them.

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.github/CONTRIBUTING.md, line 188 at r1 (raw file):

<!-- markdownlint-disable-next-line fenced-code-language -->

Would console work for the language?

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Research/ConfluenceAndCausalInvariance/ConfluenceAndCausalInvariance.md, line 19 at r1 (raw file):

> In a terminating system, causal invariance implies that whatever path is taken, the "answer" will always be the same.

> **Confluence**: A simplified form of causal invariance considered in term rewriting systems such as ones that reach fixed points.

This file tries to follow 120 characters limit (which I think we should start using at some point). Why merge the lines?

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Research/LocalMultiwaySystem/LocalMultiwaySystem.md, line 426 at r1 (raw file):

3. Consider all vertices with out-degree zero (the future boundary of the intersection):

* If the boundary contains either `A` or `B`, they are timelike separated

This should be indented by 3 spaces as a sublist of (3).

[aokellermann]

Reviewable status: 4 of 55 files reviewed, 5 unresolved discussions (waiting on @aokellermann and @maxitg)

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.markdownlint.json, line 7 at r1 (raw file):

Previously, maxitg (Max Piskunov) wrote…

Add an empty line at the end of the file.

Done.

[maxitg]

Reviewed 51 of 51 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved