* Fix a security hole that allowed insertion of unsafe content via the meta

* Fix a security hole that allowed insertion of unsafe content via the meta
  plugins's support for inserting html link and meta tags. Now such content
  is passed through the htmlscrubber like everything else.
* Unfortunatly, that means that some valid uses of those tags are no longer
  usable, and special case methods needed to be added for including
  stylesheets, and for doing openid delegation. If you use either of these
  in your wiki, it will need to be modified. See the meta plugin docs
  for details.