info-mode image alt text display (patch)

[Kevin Ryde]

I'd like to propose this change to get Info-display-images-node
showing the the text alternative parts of @image blobs, if the tty
can't show the graphics.  Such text is of course provided specifically
for when the graphics can't be shown.  It can be an ascii art
rendition, or merely a few words about what you could have seen.

2007-03-25  Kevin Ryde  <address@hidden>

        * info.el (Info-display-images-node): On a text-only terminal, show
        the "text" or "alt" parts of the image blobs.


You can see the effect on the foo.info file below.  Currently the
images are only blank lines, with my change it comes out like

        This is an alt bit.

        This is a text bit from a .txt file.

        Or if no text parts at all then you get:
        [image:foo.png]

foo.texi and bar.txt below are the sources.  Copy any random png files
to create foo.png and bar.png.

info.el.image-alts.diff
Description: Text Data

foo.info
Description: Binary data

foo.texi
Description: TeXInfo document

bar.txt
Description: Text document