Better packaging.
- Use PHP 5.4 php5{en|dis}mod.
- Scrap dh-make-php rules file and use Ondrej's packages as template.
- Breaks INI compatibilty with PHP 5.3. Don't *build* for 5.3 unless
  you're prepared to fix up config locations with Chef in prod, etc.
PHP 5.3 compatibility fixes.