- add an external method ERP5Type_getSecurityCategoryFromEntity
- change the script ERP5Type_getSecurityCategoryMapping
All of this permit to handle 'group' 'site' 'function' base categories in
security group creation. This also make the testPSJ pass because there were
all broken because of this.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@22830 20353a03-c40f-0410-a6d1-a30d3c3de9de