GLOBAL MARKETS-Markets dive on gloomy growth outlook

* World Bank cuts growth forecasts, deflation fears rise* Stocks, lower-rated bonds, commodities fall* Safe-haven Japanese yen gains ground against dollar* Legal opinion on ECB bond-buying helps trim losses* Emerging markets underperform, Russia in focusBy Lionel LaurentLONDON, Jan 14 (Reuters) - Financial and commodities markets slumped on Wednesday after the World Bank cut its growth forecasts f