(Bloomberg) -- Spot gold climbed after the Federal Reserve repeated a vow to use all tools to support the U.S. economy and extended emergency measures to ensure the global financial system has access to a ready supply of U.S. dollars.The central bank, which left its benchmark interest rate unchanged near zero, said it will extend measures including temporary liquidity swap lines. The dollar fell.Gold is heading for its biggest annual increase in a decade, driven by concern over the coronavirus p