Chrysler Group LLC is doubling down on sponsorship to promote its expanding line of Altitude limited-edition vehicles.The automaker earlier this year launched four Altitude vehicles: Compass, Grand Cherokee, Patriot and Wrangler. The vehicles feature black leather interiors, black body components and other special features.And the company is promoting the vehicles through new music and sports deals.On the music front, Jeep this year has partnered with three music festivals: The Free Press Summer...