servicedirectory: return real error when object is not found
servicedirectory: return real error when object is not found

Change-Id: I881b136e84f22eb899e3b9328a7bf3e381dc53b0

aldebaran/libqi-java,aldebaran/libqi,aldebaran/libqi,aldebaran/libqi,aldebaran/libqi-java,bsautron/libqi,aldebaran/libqi-java,vbarbaresi/libqi