core: Param uri of MediaItem.add_resource is now nullable
core: Param uri of MediaItem.add_resource is now nullable

Tarnyko/rygel,Pelagicore/Media-Manager-Rygel-patched,GNOME/rygel,Pelagicore/Media-Manager-Rygel-patched,jku/rygel,GNOME/rygel,Pelagicore/Media-Manager-Rygel-patched,jku/rygel,luisbg/rygel,Tarnyko/rygel,GNOME/rygel