Remove device num_signals property updates from signal db updates.
Remove device num_signals property updates from signal db updates.

radarsat1/libmapper,libmapper/libmapper,libmapper/libmapper,radarsat1/libmapper,libmapper/libmapper,libmapper/libmapper,johnty/libmapper,malloch/libmapper,malloch/libmapper,radarsat1/libmapper,johnty/libmapper,malloch/libmapper,malloch/libmapper,johnty/libmapper,libmapper/libmapper,johnty/libmapper,radarsat1/libmapper,johnty/libmapper,malloch/libmapper,malloch/libmapper,radarsat1/libmapper,libmapper/libmapper