* The underscore escaping support exposed a bug in edit links: Such links

* The underscore escaping support exposed a bug in edit links: Such links
  were titlepage escaped in the urls, and then doubly escaped by the CGI
  when editing. To fix this, I removed the titlepage escaping in the edit
  urls.
* That means that *every edit link* on the wiki is potentially changed.
  Rebuilding wikis on upgrade to this version therefore necessary; enabled
  that in postinst.