Fixes #295: set default client port when unable to parse port string

      }

      else {

        parsed_host_port.first = host_port.substr(0, host_end);

        try {

          parsed_host_port.second = static_cast<unsigned short>(stoul(host_port.substr(host_end + 1)));

        }

        catch(...) {

          parsed_host_port.second = default_port;

        }

      }

      return parsed_host_port;

    }