[PD] PD FLOSS manual and help patch corrections

[Ben Baker-Smith]

The last line on
http://en.flossmanuals.net/PureData/GEMImagesMoviesAndVideo says to
check out the [sig2pix~] object. The object is actually
[pix_sig2pix~].

Separately, in the help patch for [pix_movie] it recommends using the
same [colorspace RGBA( messages that work with [pix_film], but these
messages return the error:
"pix_movieDarwin: no method for 'colorspace'"

I wasn't sure who to send these corrections to, but I figured whoever
it was is probably on the list.

Thanks!

-Ben