GLOBAL MARKETS-World stocks hold gains; dollar dips on U.S. labor data, yuan surge

* Chinese numbers add to upbeat factory data in Europe, U.S. NEW YORK, Jan 5 (Reuters) - World stocks shrugged off weakness on Wall Street to cling to gains after hitting their highest level since mid-2015 on Thursday, bolstered by strong Chinese data that added to optimism about global growth and inflation. The dollar slipped against a basket of major currencies after U.S. inflation and unemployment data failed to reverse a downtrend that followed some of the biggest gains on record for China's