all widgets should be located in erp5_web_multiflex5_demo_layout, and we can just use proxy field to them as they are in erp5_web_multiflex5_layout.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@26772 20353a03-c40f-0410-a6d1-a30d3c3de9de