Sphinx-md

* adds the ability to process some kinds raw HTML in a markdown file into Docutils objects (requires Beautifulsoup). Set sphinx_md_processRaw=True to enable the feature. Useful for when you need to publish to targets other than HTML.
* tables (does not currently handle spans)
* images
* paragraphs
* changes "hidden" tag to comment in docutils.

* Minor fix for issue that caused exception when resolving links in .rst files.
* Small improvement to documentation.