OAKLAND — Seth Smith, Coco Crisp and the never-say-die Oakland Athletics forced a Game 5 of their AL division series against the Detroit Tigers with their most memorable comeback yet. Smith hit a game-tying two-run double off closer Jose Valverde in the ninth inning and Coco Crisp capped Oakland’s most dramatic comeback yet with a two-out RBI single as the A’s staved off elimination for a second straight night with a 4-3 victory in Game 4 Wednesday night. “There’s a confidence,” manager Bob Melvin said. “We’ve done it so many times so there’s always going to be that confidence until …