EBackend: Keep a reference on GNetworkMonitor.
EBackend: Keep a reference on GNetworkMonitor.

Keep a strong reference on the default GNetworkMonitor, and connect to
its "network-changed" signal.  Our signal handler does nothing for the
moment, but shortly it will update the "online" state.

Distrotech/evolution-data-server,Distrotech/evolution-data-server,matzipan/evolution-data-server,matzipan/evolution-data-server,tintou/evolution-data-server,Distrotech/evolution-data-server,tintou/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server,Distrotech/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server,Distrotech/evolution-data-server,matzipan/evolution-data-server