Introduce search key which now are reposnsible for Query generation.
Improve parsing of search strings (you must install "ply":http://www.dabeaz.com/ply/).



git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@19152 20353a03-c40f-0410-a6d1-a30d3c3de9de