By Jonathan Saul, Elisa Anzolin and Francesca Landini LONDON/MILAN (Reuters) – Sixty-five years after Aristotle Onassis founded Greece’s Olympic Airways, another shipping entrepreneur is planning to take to the skies – this time in Italy, where Gianluigi Aponte’s MSC has its sights on the successor company to Alitalia. The 81-year-old, known as “the captain” after building his shipping empire from a single vessel, is hoping to forge an air freight and passenger business to dovetail with MSC’s sea cargo and cruise operations. But there are big challenges. Alitalia stumbled for years, with the I…