If we were in the business of judging books by their covers, here’s what we would assume about the line-up at last night’s installment of the Six Points Music Festival: The Glory and the Majesty are emo, The Jaguar Club are a bunch of car enthusiasts, Life in a Hospital are bleak and brooding and Lejeune are French. Ultimately, only one of these assumptions proved correct; read on to satisfy your curiosity. First up, Arlington’s…