Convert site to a single JavaScript archive

* Convert build to use a single JavaScript file on the site (instead
  of downloading each library separately). This also means that all
  global variables (e.g., `$` for JQuery, `_` for Underscore.js) can
  be removed.
* Remove unused scripts and/or move them to a more appropriate repo
* Update the `deploy` script to work with CircleCI's automation
* Update markdown display code to allow images to be located with the
  markdown data files instead of the pre-rendered index pages

src/jade/includes/_standard_scripts.jade

@@ -5,10 +5,4 @@
 //- All rights reserved.
 //-
 
-script(src="/js/underscore.js")
-script(src="/js/jquery.js")
-script(src="/js/backbone.js")
-script(src="/js/jade.js")
-script(src="/js/markdown.js")
-script(src="/js/when.js")
 script(src="/js/main.js")