Add more generic markup types

[athanclark]

Currently, we only have JavaScript and Image as types of markup. We could make this way more pervasive:

• Styles
• Content
  • Headers
  • paragraphs
• Videos and media
• Applications - SVG, Flash, etc

The thing about these "markup" types is it expects all information to be local to a markup node - there's no javascript sources needed to initialize this markup type - there's only some text, and a few different ways to use the text, but in the end it's all internal to this node, nothing else. That's where this library is going to stay.