Gumroad, the buzzy one-man startup launched by Pinterest and Turntable app designer (and 19-year-old college dropout) Sahil Lavingia, officially launches today with over $1.1 million in seed funding from investors Accel Partners, Chris Sacca, Max Levchin, SV Angel, Josh Kopelman, Seth Goldstein, Naval Ravikrant, Collaborative Fund and Danny Rimer..