Fails to compile for Arduino Due

[jnmacdnld]

On Due, PROGMEM is not available, so when compiling for Due, the compiler complains about undefined PROGMEM macros. As a workaround, these macros could be defined in ArduinoUnit.h:

// Workaround for Arduino Due
#if defined(__arm__) && !defined(PROGMEM)
#define PROGMEM
#define PSTR(s) s
#define memcpy_P(a, b, c) memcpy(a, b, c)
#define strlen_P(a) strlen(a)
#endif

[jnmacdnld]

Closed because I made a pull request.