The world's largest bourbon festival is also a music festival. Four days in Louisville in September — the spirits and the lineup arrive at the same time. Bourbon & Beyond is the kind of festival where the person next to you at the bourbon bar is a distillery master, and the person on your other side just drove from Nashville. The festival occupies four days of Louisville's late September, when the weather is near-perfect. The food program is legitimately excellent — James Beard nominees, regional pit masters, dishes designed specifically around bourbon pairings. The music stages run simultaneously, meaning you'll make hard choices about what to sacrifice. Diehard fans treat …