Add all our specialized Markdown rendering/processing to Djblets.

Review Request #7316 — Created May 18, 2015 and submitted — Latest diff uploaded




We had a bunch of useful and complex code in Review Board to
render/style Markdown files in a more WYSIWYG-ish format (matching the
output styles/spacing to the input), generate e-mails with Markdown
styles inlined, escape/unescape content for Markdown rendering, and
perform other types of processing.

This isn't specific to Review Board, and would be very nice to reuse, so
it's now in Djblets. The utility functions live in the new
djblets.markdown module, with extensions living in
djblets.markdown.extensions.wysiwyg and

The styles for rendering the Markdown content lives in a new mixin,
which can be injected into any CSS rule the consuming project chooses.

Unit tests pass.

Tested that all the new stuff works with Review Board still (after moving over to this).