* doc/contributing.de.texi: New file. * doc/guix.de.texi: New file * doc/local.mk (TRANSLATED_INFO): Add them. (info_TEXINFOS): Add guix.de.texi. * po/doc/guix-manual.de.po: New file. * po/doc/local.mk (EXTRA_DIST): Add it. * doc/guix.texi: Document the German translation.