Refactor the uid generation to solve some complex problems. This still leaks...

Refactor the uid generation to solve some complex problems. This still leaks reserved uids if instance ids are not used for Zope, but the duplication problem should not occur any longer.


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@3048 20353a03-c40f-0410-a6d1-a30d3c3de9de