Re: mention unused_oids script in pg_proc.dat

>
> This stuff is already documented in bki.sgml. Adding an extra
> location to hint about the script may be useful to have, but
> pg_proc.dat is not a good choice as it is one catalog among many
> others. One idea: we could add a README or a README.oid in
> src/include/catalog/ telling more about unused_oids, renumber_oids and
> duplicate_oids, still it would be a duplication of what the
> documentation already informs about. Another idea could be just to
> provide a link redirecting to the "current" or "in-development" docs,
> stored in a README in src/include/catalog/.

I aggree with having more READMEs around the src tree.
It’s true that a lot of doc content found in VII. Internals is dev-oriented,
but imho it should be closer to the src (and more succinct/less verbose too).

Looking at some of the text in 67.2.2. OID Assignment for example,
a few things look outdated wrt choosing OIDs.

One can look through the history of similar commits to see what
needs to be changed; So it’s not THAT bad.
It’s just that script runs are not visible in git.