SGML doc file references

Hi,
I'm reading the docs (I'm trying to figure out some replication
things) and I was wondering why the file references [1] don't match
the file names.

Most of the inconsistent items are for `obsolete-*` where the filename
is actually `appendix-obsolete-*`. But, oddly, afaict, they were
introduced with these inconsistent names.

In one of those cases, the base of the file is also wrong (pgxlogdump
[2] vs. pgreceivexlog [3]). I believe this was an api change between
9.3 and 9.4. I know that there are `id=` tags designed to catch old
references, but the comments don't seem to serve that purpose, if they
are, I was wondering if an additional comment explaining their
discrepancies would be warranted.

In one case, it's just a missing `-` (`backupmanifest.sgml` vs
`backup-manifest.sgml`) which feels accidental.

(I do have more technical questions about the docs, but I think I may
try a different venue to ask them.)

Thanks,

[1] https://github.com/jsoref/postgres/commit/sgml-doc-file-refs
[2] https://www.postgresql.org/docs/9.3/pgxlogdump.html
[3] https://www.postgresql.org/docs/9.4/app-pgreceivexlog.html