def createPlaylist(name,description,tracks,extras=nil)
      method = 'createPlaylist'
      type = Playlist
      args = {:name=>name,:description=>description,
        :tracks=>Rdio::keys(tracks)}
      args[:extras] = extras if extras
      return_object type,method,args,true
    end
def createPlaylist(name,description,tracks,extras=nil)
      method = 'createPlaylist'
      type = Playlist
      args = {:name=>name,:description=>description,
        :tracks=>Rdio::keys(tracks)}
      args[:extras] = extras if extras
      return_object type,method,args,true
    end
Create a new playlist in the current user's collection.  The new
 playlist will be returned if the creation is successful, otherwise
 null will be returned.