Lionel Richie’s resume is probably triple the length of any other act playing the 8:00 pm time slot during Bonnaroo’s 2014 lineup, and in a lot of cases, Richie is twice the age of those other artists. He’s the old guy in the room. He gets it, and he takes it with stride and grace. To the young folks, he’s been all but reduced to a meme, the leaned-back pose with the giant afro from the “You Are” single cover art. Somebody in the front row of Bonnaroo’s main stage crowd even came dressed as this version of Richie, which the singer acknowledged with a smirk.