gflBitmapGetEXIF() does not expect multiple EXIF blocks

[AmigoJack]

I've encountered JFIF files having multiple/separate EXIF blocks. Which may be no good practice but is allowed by all standards. GFL however won't let me walk thru all fields of both, only those from the first one. If you ever release a new version please expect files to have more than one EXIF block.