Ensure that all <sect1> and <refentry> tags have IDs. This is needed

Ensure that all <sect1> and <refentry> tags have IDs.  This is needed
to ensure that the resulting webpages have predictable URLs, instead of
ever-changing numeric IDs.  The new contrib docs were the biggest
offender, but some old stuff had the problem too.  Also, rename a couple
of new contrib sgml files for consistency's sake.