Turn commercial demo page into management page

So that it doesn't need to use https.
Use jQuery for lib
Fixes components not loading sometimes
Fix DOM Exception 12 Syntax errors

Fixed these by trial and error rather than any understanding.
Remove redundant admin commercial demo page

It's now a management page in the commercial module.
Remove redundant admin commercial demo page controller
Make hardcoded json URLs environment-specific
Use pre-existing properties to make hardcoded json URLs environment-specific
Make commercial.css available from management page in dev environment
Use json instead of jsonp to fetch ad feeds into commercial demo page
Removed line from dev-build routes table.
Merge pull request #2331 from guardian/kc-comm-demo-page

Commercial demo page