Custom AuthComponent Class Added

With this the user can override Configure::Opauth['AuthComponent'] for their own custom AuthComponent Class.

eg :-  If user want to make his own AuthComponent class like

  class MyAuthComponent extends AuthComponent{

  }

then in his bootstrap file he can write 
CakePlugin::load('Opauth', array('routes' => true, 'bootstrap' => true));
Configure::write('Opauth.AuthComponent','MyAuth') ;
and OpauthController will be allowed by MyAuth