follow yams api change: attributes permissions are now defined for an 'update' action, no more 'add' / 'delete' which makes no sense in such case. fix afs.relations_by_section permissions checking of object relation on the way.

Latest changes 
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* table of `all latest changes`_

Links below is providing useful RQL query example.

.. _all latest changes: view?rql=Any+M%2CX+WHERE+X+modification_date+M+ORDERBY+M+DESC+LIMIT+30