allow to override is_primary result using an argument given to object constructor (have to be given to 'initargs' argument of .render like initargs={'is_primary': False}
update _render_attribute / _render_relation prototype to gain more control on label through uicfg (for attributes and relations). Keep bw compat for crm/iliane
fix workflow consistency: check state/transition name uniqness in the wf when state/transition name is modified ; use the new msg argument of rql constraints to have a nicer error message on failure