All three of the big YA franchises feature in cinemas this year. We’ve already had the second of the Divergent films, The Insurgent, and The Hunger Games reaches its climax in November with Mockingjay Part II. Sandwiched in between comes Maze Runner – The Scorch Trials, which is out now, certificate 12A. London Mums’ resident film critic, Freda Cooper, puts on her running shoes to catch…