pgsql: Add > o Do VACUUM FULL if table is nearly empty?

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

o Do VACUUM FULL if table is nearly empty?

Modified Files:
--------------
pgsql/doc:
TODO (r1.1485 -> r1.1486)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1485&r2=1.1486)