8x.
* Add "scan" parameter to hook(), which is used to make the hook be called
during the scanning pass, as well as the render pass. The meta and tag
plugins need to use the new scan parameter, so will any others that modify
%links.
* Now that links are calculated in a separate pass, it can also
precalculate backlinks in one pass, which is O(N^2) instead of the
previous code that was O(N^3). A very nice speedup for wikis with lots
(thousands) of pages.
* Add a shortcut plugin, inspired by Victor Moral's contributed shortcuts
plugin, but featuring a more ikiwiki-ish syntax and with shortcuts that
can be configured using a page in wiki.