If a client connects to the advertised ProtectBabyMonitor service,
attempt to service the connection.
For now, simply close the connection instead of sending data.
When the MonitorActivity is started it will create a ServerSocket.
The assigned port is then advertised over mDNS for a
"ProtectBabyMonitor" service.
Eventually, when something connects to the ServerSocket audio
data will be streamed out.
This commit adds the shell of the MonitorActivity. This activity
will register its service on the local network, wait for a connection,
then send audio data.
The StartActivity is the first activity which will be launched
in the baby monitor, and in the future will list the two main
options: become a monitor or a listener.
