added optional attribut to user field in domain model
added optional attribut to user field in domain model

fadenb/hopper.pw,asmaps/nsupdate.info,fadenb/hopper.pw,asmaps/hopper.pw,asmaps/hopper.pw,manazag/hopper.pw,asmaps/nsupdate.info,manazag/hopper.pw,fadenb/hopper.pw,manazag/hopper.pw,asmaps/hopper.pw,asmaps/hopper.pw,manazag/hopper.pw,fadenb/hopper.pw