Make "static" create a single html file with all assets

It would be cool if the index.html that was generated by `magic-reveal static` was a completely stand-alone file, so I could send it to someone else to run for me. The things I know about are:

Replace `link rel="stylesheet"` with `` tag containing CSS

Look for include statements in CSS

Replace `script src=` with contents of script file

Replace `img src=` with a [data:](http://en.wikipedia.org/wiki/Data_URI_scheme) URI

Start by tracing the `magic-reveal static` entry point and how it generates `index.html`. Check how linked stylesheets, CSS includes, script sources, and image sources are represented, then verify that the generated presentation is one standalone HTML file with inlined CSS and scripts and data URIs for images.

Written by the indexing model from the issue text.