imagetext

This code extends `image-mode' in Emacs 22 and `auto-image-file-mode' in
Emacs 21 and 22 to show text comment parts of PNG, JPEG and GIF files.
The image size is shown too (for all image types).

There's no way to edit the image text, but of course there's no way to
edit the image itself either.

Caution: The plain image modes don't change the buffer contents, so you
can save under a different filename.  But the text added here breaks
that.  In Emacs 22 `image-mode' if you switch back to raw with the usual
C-c C-c then the text extras are removed too, and hopefully it should
work to save from there.