Reviewed by GREG KING Director: Pablo Larrain Stars: Kristen Stewart, Timothy Spall, Sean Harris, Sally Hawkins, Jack Farthing, Stella Gonet, Jack Nielen, Freddie Spry. A rather bland and uninvolving speculative look at a critical three days in the life of Diana, Princess of Wales, Spencer is far from a traditional biopic. The film takes place over three days of Christmas in 1991, before Diana …