Provide way to reauthenticate

[klnusbaum]

With the new account stuff, I've provided no way to re-enter username and password if the ticket has becomes invalid. must fix this and alert the user at appropriate times when they need to reauthenticate (i.e. figure out a good way to propigate an authentication error from the PlayerCommService and the PlaylistSyncService). IN the PlaylistSyncService, I should probably do it in the same way I handle an inactive player, being kicked from a player, etc.