Re: assert pg_class.relnatts is consistent

I wrote:
> So that leads me to the attached.
> ...
> (I agree with Alvaro's thought of shortening AddDefaultValues,
> but didn't do that here.)

Pushed both of those.  I also did something with the stale comment
that Justin referred to in the initial message (it wasn't really
good practice to try to deal with both things in one thread).

I think we're done here, though maybe the difficulty of finding a clean
way to get genbki.pl to do this suggests that AddDefaultValues needs
to be redesigned.  Not sure what that'd look like.

            regards, tom lane