update ERP5Site_renderQuickSearchDialog to use ERP5Site_processAdvancedSearch to not make conflict with the top search box.
Split in many forms should be required to avoid this trick, but it's not possible to include a form in the main form. And split in many form is a very big change that will affect all sites and all projects.
So for now we will just use this trick like it is in the km.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@26395 20353a03-c40f-0410-a6d1-a30d3c3de9de