Added a security policy which is able to combine parent (for group) and no parent (for the rest). It can be useful to generate groups such as AF-ACC-MAN_NXD* (any accounting manager in Nexedi group) for users

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@14836 20353a03-c40f-0410-a6d1-a30d3c3de9de