ikiwiki version 1.29 is released.

Wikis need to be rebuilt on upgrade to this version. If you listed your wiki
in `/etc/ikiwiki/wikilist` this will be done automatically when the Debian
package is upgraded. Or use `ikiwiki-mass-rebuild` to force a rebuild.

There is a change to the plugin interface in this version. Plugins that use
`%renderedfiles will` need to be updated, as the hash's values are now arrays
of rendered files. Plugins that cause a page to render additional files
should use the new `will_render` function to register the files.

Changelog for this release:

   * Patch from Paul Tötterman to use CP in the Makefile.
   * Patch from Alec Berryman adding a http\_auth config item that allows
     using HTTP Authentication instead of ikiwiki's built in authentication.
     Useful for eg, large sites with their own previously existing user auth
     setup. Closes: #[384534](http://bugs.debian.org/384534)
   * Change %renderedfiles to store an array of files rendered from a given
     source file, to allow tracking of extra rendered files like rss feeds.
   * Note that plugins that accessed this variable will need to be updated!
     The plugin interface has been increased to version 1.01 for this change.
     As few plugins use %renderedfiles I haven't done anything else to ensure
     compatability of old plugins.
   * Add will\_render function to the plugin interface, used to register that a
     page renders a destination file, and do some security checks. Previously
     but no longer rendered files will be cleaned up.
   * Use will\_render in the inline and linkmap plugins.
   * You will need to rebuild your wiki on upgrade to this version.
   * Atom feed support based on a patch by Clint Adams.
   * Add feeds=no option to inline preprocessor directive to turn off all types
     of feeds.
   * $IkiWiki::version now holds the program version, and is accessible to
     plugins.
   * Make the aggregate plugin emphasize error messages.
   * Patch from Recai to limit recentchanges to displaying max 10 files for a
     given changeset (to avoid large number of file changes excessively
     bloating the page).