Convert an Arduino __DATE to YYYY-MM-DD

ArduinoDateToDisplayDate.ino

// Adapted from http://stackoverflow.com/questions/1765014/convert-string-from-date-into-a-time-t
// Formats __DATE__ to YYYY-MM-DD format
String ArduinoDateToDisplayDate(char const *time) { 
    char s_month[5];
    int month, day, year;
    static const char month_names[] = "JanFebMarAprMayJunJulAugSepOctNovDec";

    sscanf(time, "%s %d %d", s_month, &day, &year);

    month = (strstr(month_names, s_month)-month_names)/3;

    String monthText = month < 10 ? "0" + String(month) : String(month);
    String dayText = day < 10 ? "0" + String(day) : String(day);

    return String(year) + "-" + monthText + "-" + dayText;
}