“60 Minutes” correspondents Lesley Stahl, Bill Whitaker and Jon Wertheim said Friday that they planned to stay on at the newsmagazine, capping days of turmoil for the show. “We have had a hard time deciding whether to stay,” the three wrote in a memo to their colleagues at the program, but ultimately added: “We don’t want to see ‘60 Minutes’ die.” They wrote that they were still “deeply upset by the firings” of executive producer Tanya Simon and high-ranking producer Draggan Mihailovich, whom