Kimberly White/Getty Images for TechCrunch Peloton, the buzzy exercise-bike startup, filed for its IPO on Tuesday. Peloton’s IPO documents include a letter from CEO John Foley, who writes that Peloton "sells happiness" at its most basic level. Foley’s reasoning is that doing exercise on a Peloton bike releases endorphins, which makes people feel happy. The […]