Bug fix for auto orientation code

	modified:   FitsImage.py
	modified:   gtkw/plugins/Preferences.py
	modified:   gtkw/plugins/Thumbs.py
	modified:   qtw/plugins/Preferences.py
	modified:   qtw/plugins/Thumbs.py

Fixed buggy auto-orientation code.  Now orients JPEG images correctly
if the "Orientation" keyword is set correctly in the EXIF metadata.