Log Message:
-----------
Improve discussion of SQL functions taking/returning row types.
Modified Files:
--------------
pgsql/doc/src/sgml:
xfunc.sgml (r1.92 -> r1.93)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/xfunc.sgml.diff?r1=1.92&r2=1.93)