NORWALK, Conn. — The Priceline Group Inc. (PCLN) on Thursday reported second-quarter net income of $580.6 million. On a per-share basis, the Norwalk, Connecticut-based company said it had profit of $11.60. Earnings, adjusted for one-time gains and costs, came to $13.93 per share. The results topped Wall Street expectations. The average estimate of 11 analysts