Harry Nilsson was a constantly curious singer/songwriter who stretched out into many different areas. He did a whole album of Randy Newman songs, including “Vine Street,” a Beatles-esque two-part reminiscence about a band that never made it. He also fleshed out a world of pointy-headed cartoon people via the plinking piano and soft woodwinds of “Everything's Got 'Em,” and wrapped his soulful rasp around a stirring interpretation of “Many Rivers to Cross.”