r9739: 7 Jul 2004 Kevin Rosenberg <kevin@rosenberg.net>

        * sql/ooddl.lisp: Added SMALLINT type
        * sql/generic-postgresql.lisp: Added INT2 as SMALLINT type
        * db-mysql/mysql-objects.lisp: Added SMALLINT type
        * sql/package.lisp: Export SMALLINT
        * sql/expressions.lisp: Add MYSQL's UNSIGNED and ZEROFILL as
        db-constraints