[ REQ 5623]: thanks for geomview and gcl

[levy at math.berkeley.edu]

Folks, I hadn't until now made more than casual use of geomview and
gcl.  Now I'm much more into it, and I want to thank you for a great
product. In particular the fact that you can script things makes
geomview much more than a viewer -- it's really quite powerful and
elegant.  But of course you already knew that.

I have had some difficulty setting up matrices for camera motion in
hyperbolic mode.  I think I don't really understand the precise
meaning of terms like camera rotation, and it would be a great aid to
have a precise statement of these meanings in the manual.  I can
provide details if there is interest.

Silvio