protected RegistrationConfigurator(IContainerRegistrar registrar = null)
{
Registrar = registrar ?? new NullContainerRegistrar();
_consumers = new RegistrationCache <IConsumerRegistration>();
_sagas = new RegistrationCache <ISagaRegistration>();
_executeActivities = new RegistrationCache <IExecuteActivityRegistration>();
_activities = new RegistrationCache <IActivityRegistration>();
_endpoints = new RegistrationCache <IEndpointRegistration>();
}