From Margot Fonteyn and Rudolf Nureyev to the opium hallucination scene in La Bayadère, artist Mark Wallinger talks about how ballet had him hooked from an early ageI first saw Margot Fonteyn and Rudolf Nureyev dance when I was about seven. I remember watching them at the Royal Ballet in Swan Lake, Giselle, and Romeo and Juliet. It was thrilling and intense " the red plush seats and opera glasses, the lush sets, loo…