Sec "Upstream home page": some revisions based on discussion on policy

list

Sec "Documentation" added under Sec "Common packaging situations" for
best practices for documentation

Add tools entries for autotools-dev, dpkg-repack, alien, debsums; new
Sec "Documentation and information", add entries there for debview,
debiandoc-sgml, debian-keyring; we believe this manual now covers all
of the established, general Debian maintainer tool packages

spell-checking pass

git-svn-id: svn://anonscm.debian.org/ddp/manuals/trunk/developers-reference@1995 313b444b-1b9f-4f58-a734-7bb04f332e8d