Search function update

Ignore-this: 4cd6bddacb795ef15f133559c223ac1f

* Adds the possibility to exclude namespace(s) from search, by preceding them with "^".
* Changed handling of search parameters to allow any order of words and namespaces.

darcs-hash:20090311160255-13810-c2e00cc7764d180967b4c6f22e17b1c0dafe36f4.gz