TOKYO Japanese stocks surged and markets across Asia started strong on Friday, tracking substantial gains on Wall Street after encouraging U.S. retail sales data reassured investors about the health of the world's biggest economy. The key Nikkei 225 index added nearly three percent following rallies on Wall Street, continuing a bullish run after stocks in Tokyo crashed Monday on worries about the U.S. economy and a stronger yen. Encouraging economic growth in Japan had already spurred the