“Newport & the Great Folk Dream” is a rapturous documentary — elegant and transporting, full of scratchy lyrical black-and-white images and performances that have a timeless power. The movie tells the story of the Newport Folk Festival from the pivotal years of 1963 to 1966, and when I say that it “tells the story,” I mean that there’s a surprisingly sharp and resonant narrative at play we haven’t seen before. Murray Lerner’s 1967 documentary “Festival” covered those same years, but that film