From Wall Street Journal A deal that would have given online-gambling giant PokerStars a chance to re-enter the U.S. market turned into a legal battle Monday as a judge agreed to temporarily block investment firm Colony Capital LLC’s attempt to terminate a casino-sale agreement with PokerStars. A New Jersey Superior Court judge issued a temporary restraining order that prevents Colony from negotiating with other parties to sell its Atlantic Club casino in Atlantic City, N.J., for 10 days. A hearing is set for May 17, when the judge will consider a lengthier restraining order. PokerStars had agreed last fall to…