PARIS — Europe's new bailout fund is being unveiled as finance ministers from the 17-nation eurozone meet in Luxembourg, amid more gloomy indicators about Europe's economic health. Officially called the European Stability Mechanism, the new $653-billion rescue fund aims to offer a financial buffer for ailing eurozone economies like Greece and Spain. It follows September's announcement by the European Central Bank of a bond-buying plan to ease the longstanding eurozone debt crisis.