Support coloured output in applicable terminals

[markfinal]

Would be useful to identify output/errors from tools by colouring the output.

[markfinal]

From http://stackoverflow.com/questions/17493276/how-to-keeps-colours-from-msbuild-output

Console.ForegroundColor = ConsoleColor.White;
Console.BackgroundColor = ConsoleColor.DarkRed;
Console.Error.WriteLine(text);
Console.ResetColor();

[markfinal]

From GoogleTest, I found this (in C++)

// Helpers for printing colored strings to stdout. Note that on Windows, we
// cannot simply emit special characters and have the terminal change colors.
// This routine must actually emit the characters rather than return a string
// that would be colored when printed, as can be done on Linux.
void ColoredPrintf(GTestColor color, const char* fmt, ...) {
  va_list args;
  va_start(args, fmt);

#if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_SYMBIAN || GTEST_OS_ZOS || GTEST_OS_IOS
  const bool use_color = false;
#else
  static const bool in_color_mode =
      ShouldUseColor(posix::IsATTY(posix::FileNo(stdout)) != 0);
  const bool use_color = in_color_mode && (color != COLOR_DEFAULT);
#endif  // GTEST_OS_WINDOWS_MOBILE || GTEST_OS_SYMBIAN || GTEST_OS_ZOS
  // The '!= 0' comparison is necessary to satisfy MSVC 7.1.

  if (!use_color) {
    vprintf(fmt, args);
    va_end(args);
    return;
  }

#if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
  const HANDLE stdout_handle = GetStdHandle(STD_OUTPUT_HANDLE);

  // Gets the current text color.
  CONSOLE_SCREEN_BUFFER_INFO buffer_info;
  GetConsoleScreenBufferInfo(stdout_handle, &buffer_info);
  const WORD old_color_attrs = buffer_info.wAttributes;

  // We need to flush the stream buffers into the console before each
  // SetConsoleTextAttribute call lest it affect the text that is already
  // printed but has not yet reached the console.
  fflush(stdout);
  SetConsoleTextAttribute(stdout_handle,
                          GetColorAttribute(color) | FOREGROUND_INTENSITY);
  vprintf(fmt, args);

  fflush(stdout);
  // Restores the text color.
  SetConsoleTextAttribute(stdout_handle, old_color_attrs);
#else
  printf("\033[0;3%sm", GetAnsiColorCode(color));
  vprintf(fmt, args);
  printf("\033[m");  // Resets the terminal to default.
#endif  // GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MOBILE
  va_end(args);
}