pgsql: Fix a bunch of bad grammar in the docs: "<link>, which see for

Log Message:
-----------
Fix a bunch of bad grammar in the docs: "<link>, which see for more
information" is un-good English.

Modified Files:
--------------
pgsql/doc/src/sgml:
ddl.sgml (r1.74 -> r1.75)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ddl.sgml.diff?r1=1.74&r2=1.75)
pgsql/doc/src/sgml/ref:
alter_role.sgml (r1.7 -> r1.8)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_role.sgml.diff?r1=1.7&r2=1.8)
alter_user.sgml (r1.42 -> r1.43)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_user.sgml.diff?r1=1.42&r2=1.43)
begin.sgml (r1.35 -> r1.36)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/begin.sgml.diff?r1=1.35&r2=1.36)
create_group.sgml (r1.17 -> r1.18)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_group.sgml.diff?r1=1.17&r2=1.18)
create_user.sgml (r1.39 -> r1.40)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_user.sgml.diff?r1=1.39&r2=1.40)
createlang.sgml (r1.40 -> r1.41)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/createlang.sgml.diff?r1=1.40&r2=1.41)
drop_group.sgml (r1.13 -> r1.14)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_group.sgml.diff?r1=1.13&r2=1.14)
drop_user.sgml (r1.23 -> r1.24)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_user.sgml.diff?r1=1.23&r2=1.24)