Previously, if the parent was specified as WITH OIDS, each child
also had to be explicitly specified as WITH OIDS.

Amit Langote, per a report from Simon Riggs.  Some additional
work on the documentation changes by me.

Discussion: http://postgr.es/m/CANP8+jJBpWocfKrbJcaf3iBt9E3U=WPE_NC8YE6rye+YJ1sYnQ@mail.gmail.com