“Last night, Kendrick Lamar's long-thirsted-after new album, To Pimp a Butterfly, materialized suddenly on iTunes. It’s a prickly, restless collection, informed by (among other things) swampy mutant-funk and neo-soul psychedelia (a bit of Badu and D’Angelo, a bit of Love Below-like outright silliness). Kendrick carves his lane right down the middle of it all, channeling the trad gangsta rap of his ”