MFbed: Minor update to the German website.

www/de/about.sgml fixes only
www/de/administration.sgml 1.6 -> 1.7
www/de/mailto.sgml 1.31 -> 1.32 + fixes
www/de/share/sgml/navibar.l10n.ent 1.6 -> 1.8 + fixes

Obtained from: The FreeBSD German Documentation Project.