Log Message:
-----------
Clarify trigger function return convention, per Thomas Hallgren.
Modified Files:
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pgsql-server/doc/src/sgml:
trigger.sgml (r1.35 -> r1.36)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/doc/src/sgml/trigger.sgml.diff?r1=1.35&r2=1.36)