Tribune Publishing, the newspaper chain that includes The Chicago Tribune, The Daily News and The Baltimore Sun, said on Monday that it had begun serious discussions about a sale of the company to a pair of bidders who came through with an offer nearly two months after it agreed to sell itself to Alden Global Capital, a New York hedge fund.The new bid, which is for more than the amount offered by Alden, was made on Thursday by Stewart W. Bainum Jr., a Maryland hotel magnate, and Hansjörg Wyss, a Swiss billionaire who made his fortune as a …