extended the install_packages documentation
Removed the glossary (since it is far from being complete).
Removed features and wishlist, belongs to the package itself.
Changed the URLs and email addresses for sf.
Minor changes with regard to install-process.
Merged 1st and 2nd part of installation-process into this file.
Merged contents to 'installation-process.sgml'.
Now explains the class concept in detail.
yet another minor PRELOAD change
minor changes regarding the URI check
