Americans love a Cinderella story, almost as much as they love the indomitable American spirit.“Crazy Rich Asians,” directed by Jon M. Chu and adapted from the 2013 best-selling novel by Kevin Kwan, delivers both.What more could one ask from a frothy, formulaic, end-of-summer fairytale of star-crossed lovers?Blinding sequins? Over-the-top consumption? Dizzying exotic locations? Done.Pleasant, plucky and …