Add RemoteCommand 'status' command.

As DMRGateway, it reports connection status.

Command sent: "status" to port: 7642
dstar:n/a dmr:conn ysf:n/a p25:n/a nxdn:n/a fm:n/a

RemoveCommand has been slighlty modified, as using Log on a read-only filesystem simply forbids the strings to be displayed.
Another solution would be to set LogInitialisse's filePath to "/tmp/" for *nix systems.

DMRDirectNetwork.cpp

@@ -316,6 +316,11 @@ bool CDMRDirectNetwork::writeTalkerAlias(unsigned int id, unsigned char type, co
 	return write(buffer, 15U);
 }
 
+bool CDMRDirectNetwork::isConnected() const
+{
+	return (m_status == RUNNING);
+}
+
 void CDMRDirectNetwork::close()
 {
 	LogMessage("Closing DMR Network");