Prevent crashes when loading .reg lexer:

For some reason when using python2 you get this in get_all_lexers()

('reg', (), ('*.reg',), ('text/x-windows-registry',))

colout/colout.py

@@ -241,7 +241,7 @@ def load_lexers():
             try:
                 lexers.append(lexer[1][0])
             except IndexError:
-                logging.warning("cannot load lexer: %s" % lexer[1][0])
+                logging.warning("cannot load lexer: %s" % lexer[0])
                 pass
             else:
                 logging.debug("loaded lexer %s" % lexer[1][0])