By Denny Dyroff, Entertainment Editor, The Times  People’s Light If it’s December, “A Christmas Carol” must be on the calendar of live theaters around the area. It’s a time-worn holiday tradition. This year, People’s Light (39 Conestoga Road, Malvern, peopleslight.org) is presenting a production of Charles Dickens’ “A Christmas Carol” now through January 4 on the Leonard C....