Reuters: Nissan Motor Co took the wraps off its much-awaited electric car on Sunday, naming the hatchback “Leaf” and taking a step toward its goal of leading the industry in the zero-emissions field. Japan’s No.3 automaker and its French partner, Renault SA, have been the most aggressive proponents of pure electric vehicles in the auto industry, announcing plans to mass-market the clean but expensive cars globally in 2012. Nissan will begin selling the first Leaf cars in the United …