Index small cleanup

[mauriciopoppe]

As part https://github.com/maxogden/requirebin/issues/19 I wanted to move some code out of index.js

changes:

• since jQuery is used in the app I tried to use it instead of elementClass
• the editors are now in lib/editors.js :)
• triggering a bundle request is now based on the content of the editors and it's only done if the editor has been edited, as a result md5 is no longer needed (I'm using CodeMirror's dirty detection instead)
• some ui code is now moved to ui-controller, sadly I couldn't move actions because all the functions rely too much on the contents of index.js :(

[max-mapper]

+1. sorry about my code quality :{