Add shopping cart consistency check.
New naming style for PT applied.
Rework some forms/scripts to be more general so it's possible that they can be moved to erp5_web.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@12819 20353a03-c40f-0410-a6d1-a30d3c3de9de