graphics15.diff

[Angus Leeming]

Herbert, I have commented this out of getExtFromContents as it crashes on my 
machine. Do chars '\000' exist?

//                  else if ((str.at(3) == 'i') && (str.at(0) == '\000') &&
//                           (str.at(1) == '\000') && (str.at(2) == '\000'))
//                      return "xwd";

Angus