ESCAPE=HTML for titles in the templates for these feeds, and instead
escape the title going in to the template. Previously, the title was
sometimes double-escaped in a feed (if set via meta title), and sometimes
not (if set from the page filename).
* In the meta plugin, when a title is set, encode the html entities in it
numerically. This works better in the current landscape of a rss spec that
doesn't specify encoding, and variously broken feed consumers, according
to <http://www.rssboard.org/rss-profile#data-types-characterdata>.
* 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.