Bundle phing/phing and moult/contact as deps
Fix CMS bugs

* PHP Tidy now recognises HTML5 aside tags
 * PHP Tidy now doesn't mangle UTF8 characters
 * Typo in the <style> replace regex fixed
 * More reliable URL address replacement fixed
Clean up phing buildfile and isolate variables
Mark driver properties as protected to make it easier to extend
Decouple configure phase from build phase

This allows you to configure the current directory, and thus run a live
version of the site from the git checkout rather than deploying each
time.