Like a snarling beast charging towards its unsuspecting prey, the all-new 2012 Jaguar XKR-S is a startling automotive predator. Yes, you heard right: Jaguar. The brand that’s been more recently known for quiet refinement, sophistication and comfort has shredded its three-piece suit and gone feral. If you craved speed in the not-so-distant-past, a Jaguar dealership …