Do queue new activities even if there is already activities on same object with same method id but with different tag.
Add a unit test for this feature (and general behaviour of the key function behind this).


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@13415 20353a03-c40f-0410-a6d1-a30d3c3de9de