HUGH MASEKELA Jabulani [Razor & Tie] As far as most Americans are concerned, Hugh Masekela was a one-hit wonder who scored a fluke pop chart-topper in 1968 with his jazzy take on the grooving “Grazing in the Grass,” and hasn’t done much since. In truth, the South African trumpeter, flugelhornist and vocalist has been recording and performing steadily for some five decades now—and if his public profile isn’t as high as it once was,...