pgsql: Add: > > * Fix problem when multiple subtransactions of the same

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

* Fix problem when multiple subtransactions of the same outer transaction
hold different types of locks, and one subtransaction aborts

http://archives.postgresql.org/pgsql-hackers/2006-11/msg01011.php
http://archives.postgresql.org/pgsql-hackers/2006-12/msg00001.php

Modified Files:
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pgsql/doc:
TODO (r1.2060 -> r1.2061)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.2060&r2=1.2061)
pgsql/doc/src/FAQ:
TODO.html (r1.561 -> r1.562)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/FAQ/TODO.html.diff?r1=1.561&r2=1.562)