replace dead link to wisc.edu by github in docs subdirectory

[rmathar]

Closes #109 by updating a dead link documented in the latex files.

[esabol]

Another option would be to use archive.org....

https://web.archive.org/web/20250402092933/https://vdt.cs.wisc.edu/

[rmathar]

Another option would be to use archive.org....

https://web.archive.org/web/20250402092933/https://vdt.cs.wisc.edu/

but all the links in that archived web page are dead...

[esabol]

but all the links in that archived web page are dead...

So go back further to when they aren't.

[rmathar]

but all the links in that archived web page are dead...

So go back further to when they aren't.

It's not the purpose of the cfitsio links to be an archaeological digging ground for people interested in data structutures. The github pages are probably staying for a while longer (until this messaging system is forgotten by all people interested), so I'm sticking to these.

but all the links in that archived web page are dead...

So go back further to when they aren't.
It's not the purpose of the cfitsio documentation to be a digging ground for people interested in obsolecent message structures. The github sources are probably staying for a little bit longer, so they are the ones to replace the dead links.

[esabol]

Well, https://github.com/globus/globus-toolkit is not the "Virtual Data Toolkit web page". Globus was only one of the components of the Virtual Data Toolkit. If anything, https://github.com/globus/globus-toolkit should replace the www.globus.org URL a couple lines above it. Try going to www.globus.org and finding any mention of the Globus Toolkit. You won't find it, I think. https://github.com/globus/globus-toolkit is the closest thing to a "globus toolkit web page". Maybe what's needed is more extensive changes, such as from this:

DEPENDENCIES: Globus toolkit (2.4.3 or higher) (GT) should be installed.
There are two different ways to install GT:

1) goto the globus toolkit web page www.globus.org and follow the
   download and compilation instructions;

2) goto the Virtual Data Toolkit web page http://vdt.cs.wisc.edu/
  and follow the instructions (STRONGLY SUGGESTED);

to this:

DEPENDENCIES: Globus Toolkit (GT) version 2.4.3 or higher should be installed.
Download a release from the Globus Toolkit GitHub repository at
https://github.com/globus/globus-toolkit and follow the instructions to compile
and install.