Added support for rendering xexprs directly and better error handling
Added support for plugins to register pre/post render events
Moved code to codeblock
Added several placeholder plugins that I (will) use on my own blog
Added plugin to generate footnotes

Uses post-render plugins to add the footnotes to the bottom
Uses new xexpr rendering to correctly render footnotes
Added ranking (mostly for movie reviews)

Uses shared state that requires posts be sorted to generate lists dynamically