An alternative guide to this year’s cinematic offerings, we trawl through the dilapidated rows of seats in the back alley ‘art’ cinemas and crumbling picture palaces so you don’t have to; rescuing gummy Venus de Milos from sticky crevices and fishing midget gems out of cold cups of tea. Diaries at the ready cinephiles. Documentary filmmaker Amy Berg (West of Memphis, Prophet’s Prey) turns her investigative camera inwards onto the all too brief life of rock icon Janis Joplin for her new film, Janis: Little Girl Blue, profiling not just the career of one of rock music’s first and still…