break nptables on block-level structures

[UziTech]

Marked version: master

Markdown flavor: GitHub Flavored Markdown

Description

This PR copies #1598 to add breaking block-level rules to nptable (tables that don't start or end with a pipe)

e.g:

# nptable

 abc | def
 --- | ---
  1  |  2
  3  |  4

# table

| abc | def |
| --- | --- |
|  1  |  2  |
|  3  |  4  |

I also removed allowing setext header from breaking a table since it doesn't break on github. We can change it later easily if github changes. see #1598 (review)

Contributor

• Test(s) exist to ensure functionality and minimize regression (if no tests added, list tests covering this PR).

Committer

In most cases, this should be a different person than the contributor.

• Draft GitHub release notes have been updated.
• CI is green (no forced merge required).
• Merge PR

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[styfle]

Thanks!

[UziTech]

@joshbruce could you review this so we can release v0.8.1

[joshbruce]

So glad to see all the tests.