* Add feeds=no option to inline preprocessor directive to turn off all types
of feeds. feeds=rss will still work, and feeds=atom was also added, for
fine control.
* $IkiWiki::version now holds the program version, and is accessible to
plugins.
* Add permalink and author support to meta plugin, affecting RSS feeds
and blog pages.
* Change titlepage() to encode utf-8 alnum characters. This is necessary
to avoid UTF-8 creeping into filenames in urls. (There are still
some other ways that it can get in.)