Bloomberg: Electricite de France SA, the world’s biggest nuclear utility, agreed to buy British Energy Group Plc for a sweetened 12.5 billion pounds ($23 billion) as the U.K. turns back to atomic power after decades of neglect. EDF will pay 774 pence a share for the country’s biggest electricity producer, according to a statement today. That’s 35 percent above British Energy’s closing price on March 14, the last trading session before the East Kilbride, Scotland-based utility said it may receive …