Pass character used for thematic break (hr) to render function

[r0the]

Expectation

Markdown allows to use three different characters (-, *, or _) for thematic breaks (hr). I'd like to customize the output of the hr() render function depending on the character used.

I'd expect the following markdown to cause the function calls

• hr('-')
• hr('*')
• hr('_')

---
***
___

[Feder1co5oave]

+1
This could go the right way for extensibility and developer experience @joshbruce

[joshbruce]

Closing as not part of the current focus - flagged for possible future consideration. See #1106 and #1216