Stock-pickers have lamented that calm markets and not enough disparity in equity prices have hindered their ability to make money. They haven’t beaten the stock market annually in almost a decade. Industry titans like John Griffin and Alan Fournier have closed down. But now that volatility is back and fiercer than it’s been in years, hedge funds can no longer blame calm markets for their woes. A raft of issues -- rising interest rates, potential trade wars, a possible Facebook crackdown -- will likely keep stock prices moving more freely, giving managers ample opportunity to profit on the swings.