pgbouncer - pgbouncer: update todo list

Log Message:
-----------
update todo list

Modified Files:
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pgbouncer/doc:
overview.txt (r1.2 -> r1.3)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbouncer/pgbouncer/doc/overview.txt.diff?r1=1.2&r2=1.3)
todo.txt (r1.5 -> r1.6)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbouncer/pgbouncer/doc/todo.txt.diff?r1=1.5&r2=1.6)