Download track to the user's library.
(songbird.webPlaylist.mediaList = siteLib)
(songbird.webPlaylist.mediaList = siteList)
(songbird.webPlaylist.mediaList = songbird.downloadList)
(songbird.downloadList.add())
(songbird.downloadList())
(songbird.downloadItem())
(songbird.downloadSelcted())
(songbird.mainLibrary.add())
(songbird.mainLibrary.add())