libxml geekstuff

Thanks to Daniel’s revamped libxml2 API docs build system, I’ve been able to start picking my way through fixing a bunch of nagging little things that needed fixing – missing documentation for macro definitions, mostly. Not particularly stimulating work, but it’s been needed for a while, and it’s pretty mindless, a more productive use of brain-dead time than pulling down the “games” menu and saying, “Hey, wonder what this one does?”