* CLMenuInterface - All CLMenu children need to extend CLMenu and
implement this interface. This will allow us to have a standard way to
build menus and access submenus in the system
* CLInterface - moved instances of CLDownloadMenu, CLPodcastMenu and
CLPreferencesMenu to the child array in CLMainMenu
* CLPodcastMenu, CLDownloadMenu, CLPreferencesMenu - now have their main
classes passed in for manipulation.