for extended pagespecs. The old calling convention will still work for
back-compat for now.
* The calling convention for functions in the IkiWiki::PageSpec namespace
has changed so they are passed named parameters.
* Plugin interface version increased to 2.00 since I don't anticipate any
more interface changes before 2.0.
previous ugly hack used to avoid writing rss feeds in previews.
* Fix the img plugin to avoid overwriting images in previews. Instead it
does all the work to make sure the resizing works, and dummys up a resized
image using width and height attributes.
* Also fixes img preview display, the links were wrong in preview before.
joey