Update refpage category index

[oddhack]

Per #1121, the category index for the reference pages (the file man/toctail) has not been updated for the current state of the refpages. Some extension and API pages are missing. As this file is not autogenerated, this is going to be an ongoing problem so I suggest two fixes:

• Update toctail for the current refpage set - this is for @bashbaug
• Create a CI script to check the contents of toctail against the generated refpages and report inconsistencies - I'll take a swing at this if you like. You might want to wait until the script is working before updating toctail.

While it is in principle possible to go further and autogenerate the category index, this would require tagging each reference page with the categories it belongs to, as this is probably tricky to infer from the existing metadata. That seems like a lot of additional work with updates to spec sources, scripts, refpage extraction script, and maybe XML needed.