Converted serverPreferences.php to a class, Config.php.

Simplified the syntax for reading preferences:
* pref_getSectionPreference('foo', 'bar') is now Config::get('foo.bar')
* pref_getServerPreference('foo') is now Config::get('global.foo')




git-svn-id: http://voronet.francu.com/repos/DEX@1026 8d550267-2627-4c68-899f-85492a8dd5ca