[ibreadcrumb] fix breadcrumb adapter backward compat

[selectors] modify workflow selectors: is_in_state, on_transition - factorize `is_on_state` selector - add new `on_transition` selector Especially useful to match pending transitions to enable notifications when your workflow allows several transition to the same states. Note that if workflow `change_state` adapter method is used, this selector will not be triggered. In debug mode: These both selectors will check against the entity current workflow if expected values given in selector argument are valid. ValueError exception will be raised for unmatching state/transition names against the current workflow (generic etype workflow). (check against custom workflow is not implemented)

[cw-ctl] use default `mkdtemp()` behaviour to store backup file internally When using `mkdtemp(dir=instbkdir)`, a dedicated system user which hasn't the permissions to write in /var/lib/cubicweb/instances/$INSTANCE/backup will not be able to run the db-dump command.