As the automakers figure out how to improve their cars, it takes a lot to redesign HARDWARE. But it is a measure of the misplaced self-confidence of both GM and Nissan that after 11 months, including service recalls for minor issues, neither has delivered a SOFTWARE upgrade to address the most obvious shortcomings we read about all the time at plugincars.com, mynissanleaf.com and gm-volt.com and in