That's the beauty of it, I didn't do any mapping.
- I found the source tab of the MediaWiki
- I pasted it into the gist
- I named the file xyzzy.mediawiki
- GitHub formats the mediawiki source for me.
Repeat: I did *not* do any format conversions. The GitHub gist has the raw wikimedia *source* text in it!
I only noted what *needs* to be changed: some extraneous "&" and differences in how GitHub creates <a name> elements based on the different section headers. But that's a *lot* less than actually converting the source to Markdown, even with tools like pandoc...