Martin Scorsese's second feature, an exploitation picture made on assignment for drive-in mogul Roger Corman, has long been undervalued — a new 4K UHD edition celebrates it in the context of the director's body of work. In Rebecca Miller ‘s superb recent documentary “ Mr. Scorsese ,” Martin Scorsese tells a story about his 1972 exploitation film “ Boxcar Bertha ” that has become a kind of universally accepted origin story for Scorsese’s birth as an artist. In the anecdote, Scorsese shows “