pgsql: Some more small improvements in response to 7.4 interactive docs

Log Message:
-----------
Some more small improvements in response to 7.4 interactive docs comments.

Modified Files:
--------------
    pgsql/doc/src/sgml/ref:
        create_table_as.sgml (r1.28 -> r1.29)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_table_as.sgml.diff?r1=1.28&r2=1.29)
        delete.sgml (r1.21 -> r1.22)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/delete.sgml.diff?r1=1.21&r2=1.22)
        drop_group.sgml (r1.9 -> r1.10)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_group.sgml.diff?r1=1.9&r2=1.10)
        insert.sgml (r1.28 -> r1.29)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/insert.sgml.diff?r1=1.28&r2=1.29)
        select_into.sgml (r1.32 -> r1.33)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/select_into.sgml.diff?r1=1.32&r2=1.33)
        update.sgml (r1.31 -> r1.32)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/update.sgml.diff?r1=1.31&r2=1.32)