A Kennedy-crazed Princess Diana was obsessed with becoming America's first lady - and plotted to use her torrid affair with a mysterious, older, New York billionaire to pull off the sensational scheme, the tragic royal's butler reveals in his explosive new book. "She had it all dreamed out in her head - how she would redecorate the presidential apartment and become 'the new Jackie O,' " Paul Burrell writes in "The Way We Were: Remembering Diana," which hit bookstores yesterday. Despite persistent rumors, Diana never had an affair with John F. Kennedy Jr., whom she considered intellectually challenged, Burrell scoffs....