Remove emacs info from footer of SGML files.

doc/src/sgml/advanced.sgml

doc/src/sgml/arch-dev.sgml

doc/src/sgml/backup.sgml

doc/src/sgml/biblio.sgml

doc/src/sgml/bki.sgml

doc/src/sgml/catalogs.sgml

doc/src/sgml/charset.sgml

doc/src/sgml/client-auth.sgml

doc/src/sgml/config.sgml

doc/src/sgml/datatype.sgml

doc/src/sgml/datetime.sgml

doc/src/sgml/dfunc.sgml

doc/src/sgml/diskusage.sgml

doc/src/sgml/docguide.sgml

doc/src/sgml/ecpg.sgml

doc/src/sgml/extend.sgml

doc/src/sgml/external-projects.sgml

doc/src/sgml/features.sgml

doc/src/sgml/func.sgml

doc/src/sgml/geqo.sgml