Posted by Jane Murphy Look! Lily Allen\’s ditched her recent high-fashion look and gone back to her trademark prom-dress-and-trainers ensemble. Only joking, folks! In fact, it\’s Radio One DJ Nick Grimshaw who dressed up as little Lily for a party thrown by Mark Ronson in London last night. Oooh - what japes! So which look do you prefer? Nick\’s polka dots and Nikes - or Lily\’s OTT Dolce & Gabbana gown from the GQ Men …