Kramdown Metadata Parsers

Kramdown extension for parsing Markdown with a YAML preamble, for example

---
title: Now With Fresh Metadata
date: 2014-10-11
---

## Good stuff

*right*?

Adds four new parsers, analogous with the ones included with Kramdown: MetadataKramdown, MetadataMarkdown, MetadataGFM, MetadataHTML. Use as you would use built-in formats, just make sure this gem is in your load path (i.e. add it to your Gemfile)

doc = Kramdown::Document.new(markdown, input: 'MetadataKramdown')
doc.root.metadata # => {:title => 'Now With Fresh Metadata', :date => '2014-10-11'}
doc.to_html