COB-4: placeholder implementation of description()

RTCP/Cobalt/InputProc/src/Station/PacketStream.h

@@ -136,6 +136,11 @@ namespace LOFAR
         THROW(NotImplemented, "Writing to PacketStream is not supported");
       }
 
+      virtual std::string description() const {
+        //TODO: fill in all the packetstream details
+        return "PacketStream ";
+      }
+
     private:
       PacketFactory factory;