In particular, the intro movie now exits immediately again rather than staying indefinitely.
The important difference is to send the completion callback in plBinkPlayer::NextFrame(), i.e. act as if we had reached the end of the movie.
Storing the filename is to keep plClient::IHandleMovieMsg() from deleting and recreating the plBinkPlayer on every message.
The changed return values are just to better match the previous behavior and probably don?t matter.
