def wait_for_instance_death(instance, opts={})
      wait_for_instance_status(:terminated, instance, opts) if instance.exists?
    rescue AWS::EC2::Errors::InvalidInstanceID::NotFound
    end
def wait_for_instance_death(instance, opts={})
      wait_for_instance_status(:terminated, instance, opts) if instance.exists?
    rescue AWS::EC2::Errors::InvalidInstanceID::NotFound
    end
Being serial shouldn't be much slower as we are blocked by the slowest stopper anyway