Soulless, mechanical and delivered with a sense of resigned obligation second only to the “Divergent” franchise, “Fifty Shades Darker” skulks into cinemas with all the romance and fantasy of a discarded Mills & Boon paperback fished out of a sewer. Anastasia Steele (Dakota Johnson) is living her life when Christian Grey (Jamie Dornan) returns to control and manipulate it in a series of creepy yet…