It’s easy to see why filmmaker Robert Mugge is flying high these days. Five of his films, including The Kingdom of Zydeco, Rhythm ’n’ Bayous: A Road Map to Louisiana Music, and most recently, 2015’s Zydeco Crossroads: A Tale of Two Cites, were released in March on Blu-ray and DVD. Two films, Iguanas in the House, a 27-minute documentary about New Orleans’ roots-rocking the Iguanas, and Rosie’s in the House Tonight, a 55-...