Demo installation guide

[Matt.Wilkie]

> The MapServer demo installation guide is now available at
> http://mapserver.gis.umn.edu/demo_readme.html.  It is also 
> accessible from the documentation page of the MapServer web 
> site.  Thanks to  all of you who gave comments and suggestions.  
> Thanks especially to Matt Wilkie who provided additional text 
> on error messages and debugging.

I'd just like to add I wrote the error message/debugging 
section but can't really be said to be the author. It was 
Daniel Morrisette who figured out the "GD no .GIF" problem,
Frank Koorman who let me know you can't load demo.html 
because it's a template, and Stephen Lime who confirmed 
how to extract the line number from the error message.

 I felt I had to add a qualifier, because seeing all those 
words I wrote "in print" there makes it sound like I 
understand more than I do. I'm just bumbling along in the 
dark and keeping notes. :-)

cheers,

-matt