WASHINGTON (AP) - A group of automakers and energy companies will develop and build hydrogen fuel cell vehicles in a multimillion-dollar partnership with the government, aiming for possible mass marketing of the vehicles within 15 years, Energy Secretary Samuel Bodman said Wednesday. The marketing will start in California. His department announced plans for several "learning demonstration teams" involving automakers General Motors Corp., DaimlerChrysler AG, Ford Motor Co., Hyundai Motor Co. Energy companies ChevronTexaco, BP, and Shell. Ballard Power Systems, a leading manufacturer of hydrogen fuel cells, will also join in the partnership. "If our research program is successful, it is...