Gulp support

[derek-watson]

I'd like to be able to run Guide Dog as part of my asset compilation stage, through Gulp or Sprockets. Currently, Guide Dog makes the following assumptions:

• It will be run in a browser as a jQuery plugin
• It will make a single ajax request for a stylesheet with inline comments
• It will inject the built Guide Dog UI directly into the DOM

What if we broke the single src/js/guidedog.js into pieces:

• Core modules for parsing comments from blocks of stylesheet text (css, sass, stylus, pure comments, whatever) and building template data structures
• The source assets for the end-user interface
• A jQuery plugin for compiling the application UI in the browser at runtime (current behaviour)
• A Gulp plugin for compiling the application UI statically on disk

The core modules will have to be written to work in any js environment, but if that pans out we should be able to do plugins for Grunt, Assetic (php asset pipeline) or whatever else people are using.