Allow SDK to handle both wchar_t and char logging
 - created Log(char) implementation
 - Wrapped all logging in #ifdef _DEBUG
 - Replaced wchar_t * with std::wstring in HardwareSerial
 - Corrected HardwareSerial constructor variable initialization
 - Move HardwareSerial constructor/destructor implementations to .cpp
Updated build-nupkg.cmd to reflect license.txt move