CDN .org template (Fix #220)

We've finally updated the main `joomla.org` template to work with the CDN, so I've taken a crack at implementing it here.  General notes:

- Our media (hacks to the template and custom stuff) are now in `www/jtracker/core/css/jtracker.css` and should hopefully include everything (I mainly used the commit history to verify it, and it looks fine on my local; could use an extra review though)
- The template.css file is updated to the latest main template version with our hacks backed out
- If the useCDN option is enabled, the CDN template resources are preferred versus the local media