changed CharacterDataViewModel to ByteDataViewModel,
added Unit Tests for ExtendedByte Conversion,
refactored CommunicationDataViewModel,
changed from reading chars to reading bytes in SerialProtocol,
fixed Clear functionality of MultiFormatDataView
clearly defined data structure with interfaces,
implemented MultiFormatDataView so that it cooperates with a CommunicationDataViewModel,
implemented changes in SendReceiveView and TerminalViewModel,
removed DataViewModelToStringConverter since it is not used anymore