Tara Conlan An interview with John Lennon’s murderer and the UK’s first kidnapping case are being explored in new films unveiled by Sky for its recently-launched Sky Documentaries channel.The programs were unveiled as Sky UK and Ireland managing director of content Zai Bennett said the Comcast-owned broadcaster is focusing on building its brands by getting in early with creators to help it in the “arms race” of content, particularly in drama.Speaking at the Edinburgh TV Festival, Sky’s director