Add SGML file.

doc/src/sgml/ref/allfiles.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/allfiles.sgml,v 1.51 2002/12/06 03:42:52 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/allfiles.sgml,v 1.52 2002/12/06 04:40:36 momjian Exp $
 PostgreSQL documentation
 Complete list of usable sgml source files in this directory.
 -->
@@ -38,6 +38,7 @@ Complete list of usable sgml source files in this directory.
 <!-- SQL commands -->
 <!entity abort              system "abort.sgml">
 <!entity alterDatabase      system "alter_database.sgml">
+<!entity alterDomain        system "alter_domain.sgml">
 <!entity alterGroup         system "alter_group.sgml">
 <!entity alterTable         system "alter_table.sgml">
 <!entity alterTrigger       system "alter_trigger.sgml">