Support Github-style ``` code ``` code blocks

[adamnovak]

I have a schema defined in AVDL which makes heavy use of backtick-delimited preformatted code blocks for ASCII art. Avrodoc does not interpret these correctly at all.

I think the problem is that they are a Github extension. Would they be difficult to support?

[ept]

This depends on the Markdown parsing library that's bundled with Avrodoc. evilstreak/markdown-js#41 is an open issue, suggesting that the library doesn't currently support the Github dialect of Markdown.

If you want to contribute this, it would be very welcome!