(© Glyndebourne Productions Ltd. Photo: Tristram Kenton)  Lash your picnic baskets to the deck: Benjamin Britten’s “Billy Budd” — the tangled morality tale of innocence and cruelty aboard a Napoleonic-era Man-of-War with words by E.M. Forster and Eric Crozier — has set sail once again at the Glyndebourne Festival. Michael Grandage’s production from 2010 was the company’s first staging of {…}