* First to retain crown since Indurain * Frenchman Bardet finishes second * Germany's Greipel wins last stage (Adds details, quotes) By Julien Pretot PARIS, July 24 (Reuters) - Briton Chris Froome cemented his status as one of the greatest Tour de France riders when he secured his third title on Sunday after a three-week rocky ride. Germany's Andre Greipel won the 21st and last stage, a 113-km ride from Chantilly ending on the Champs Elysees in Paris. Team Sky rider Froome survived two crashes and even a jog up a mountain road to add to his 2013 and 2015 triumphs and become the first rider to retain his title since Spaniard Miguel Indurain in 1995. More...