Refactoring and beginnings of glyph support

This is still very much in the experimentation and proof of concept stage, but it has been refactored to the point where hopefully some other developers can contribute to it. I've also added plenty of notes in the Readme file.

see the readme at https://github.com/micahcondon/hummingbird for more details

see http://micahcondon.github.io/hummingbird/ to view the current glyph and rendering output