Improve [memcpy](https://github.com/gabryelreyes/SerialMuxProt/blob/757cb21ed139f70bb0a1cf3bf6eb0b4fdd5d7799/src/SerialMuxProtServer.hpp#L579) on send. Because we send synchronous and the stream will copy the data again. Issue first opened in https://github.com/BlueAndi/RadonUlzer/issues/4 but this library has become independent since then.