pgsql: Remove completed items, and the last is unwanted: < o Fix

Log Message:
-----------
Remove completed items, and the last is unwanted:

< o Fix memory leak from exceptions
<
< http://archives.postgresql.org/pgsql-performance/2006-06/msg00305.php
<
< * Allow constraint_exclusion to work for UNIONs like it does for
< inheritance, allow it to work for UPDATE and DELETE statements, and allow
< it to be used for all statements with little performance impact
<
< * Add estimated_count(*) to return an estimate of COUNT(*)
<
< This would use the planner ANALYZE statistics to return an estimated
< count.
< http://archives.postgresql.org/pgsql-hackers/2005-11/msg00943.php

Modified Files:
--------------
pgsql/doc:
TODO (r1.2039 -> r1.2040)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.2039&r2=1.2040)
pgsql/doc/src/FAQ:
TODO.html (r1.541 -> r1.542)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/FAQ/TODO.html.diff?r1=1.541&r2=1.542)