Fashion is having a full-blown Gianni Versace moment - from Donatella's supermodel reunion during her Milan Fashion Week tribute to her brother, to a huge sale of Versace vintage pieces hitting FarFetch this week. Sale curator William Vintage explains the secrets behind the Gianni magic in our exclusive video... Seeing The Fabulous Five (that's Cindy, Claudia, Helena, Carla and Naomi) slinking down the Versace catwalk, the lights of a …