Text to HTML: Difference between revisions

This task seems like it's very under-defined, but the discussion seems to be headed towards a simple markdown specification. I therefore do this with a small interface to [https://github.com/jgm/cmark cmark] to render [http://commonmark.org/ commonmark] text.

(Note that this is not some cooked code, it's coming from code that I'm using to render class notes, and hopefully it will be useful to have such an example here. It cetrainly seems to me as a useful thing compared to some half-baked not-really-markdown-or-anything implementation.)