lxml/lxml — pull request #123 by kernc (2013-06-07 13:30:18+00:00)
Title: add html5_tags to lxml.html.defs

HTML5 tags are valid HTML tags. Otherwise `lxml.html.clean.Cleaner` silently strips them if it's set with `remove_unknown_tags=True`.

I will happily extend the tests if you desire?