This fixes the irregular dark fringes around light text when not exactly pixel-aligned that are caused by independent interpolation of color and alpha. It also makes calculations simpler for things to come.
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.
Add support for external resource Cursors.
Add support for external resource Progress Linking Book.
Add support for external resource Voice Chat indicators.
