[pdftex] pdftex manual LaTeX conversion for 2024

[Karl Berry]

    svn on https://tug.org/svn/pdftex/branches/stable/ but it errored
    "Redirect cycle detected for URL")

Just for the record: it should work with the svn protocol instead of https.
svn://tug.org/svn/pdftex/branches/stable/

Or to get just the manual and not the big source tree:
svn://tug.org/svn/pdftex/branches/stable/doc/manual/

>From the command line, it would be "svn co svn://tug.org/...".

Anyway, I made a couple more tweaks to the pdftex manual along your
suggested lines to get it closer to tagging. Maybe in another release or
two it will be ready.

Best,
Karl