Log Message:
-----------
Minor documentation improvements for new string_agg aggregate.
Modified Files:
--------------
pgsql/doc/src/sgml:
func.sgml (r1.499 -> r1.500)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml?r1=1.499&r2=1.500)