Cosmetic changes
[Big one]: preview.loadJson simplified immensely ..

However, this also means that every RABL file that created
a JSON before has had to be partly / wholly re-written to pass
the new JSON
Merge branch 'master' of https://github.com/abhinavc/web-application

Includes changes related to new preview

Conflicts:
	app/assets/javascripts/students/response.js.coffee