NSScanner bug fixed

Hi,

I think I found a bug in NSScanner.m in core20010606/base/Source.

When calling scanHexInt on a string containing just "0", scanning fails. I  
suggest changing

 if (_scanLocation < myLength())
    {
      switch (myCharacter(_scanLocation))
	{
	  case '+':
	    _scanLocation++;
	    break;
	  case '-':
	    negative = YES;
	    _scanLocation++;
	    break;
	}
    }

to

 if (_scanLocation < myLength())
    {
      switch (myCharacter(_scanLocation))
	{
	  case '+':
	    _scanLocation++;
	    break;