pgsql: >>This patch adds another plpgsql trigger example to the chapter.

Log Message:
-----------

This patch adds another plpgsql trigger example to the chapter. It uses
the emp table again, but shows how to audit changes into another table
(emp_audit).

Mark Kirkwood

Modified Files:
--------------
pgsql/doc/src/sgml:
plpgsql.sgml (r1.49 -> r1.50)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/plpgsql.sgml.diff?r1=1.49&r2=1.50)