Fixed #7679 -- Added (configurable) highlighting colors to the development...

Fixed #7679 -- Added (configurable) highlighting colors to the development server. Thanks to Rob Hudson, hunteke, and Bastian Kleineidam for the various patches that contributed to the final result.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12085 bcc190cf-cafb-0310-a4f2-bffc1f526a37