Josh Penn, the Academy Award-nominated producer behind “ Beasts of the Southern Wild ,” has launched Serenade , a new production company focused on documentary and narrative films. Serenade’s first film, “The Oldest Person in the World,” was directed by Sam Green and premiered at Sundance this year where it earned an enthusiastic critical reception. Penn’s credits include “Monsters and Men,” “32 Sounds” and “The White House Effect,” the latter of which earned two Emmy nominations. Serenade launches with a slate of more than a dozen films already in various stages of development, production, and post-production, including on the fiction side “Dave, Dave, Ruth & Dave,” directed by Alex Fischer, who was behind “Wicker,” and Rachel Wolther; “Here for the Weekend,” the debut of Jane Casey Modderno; and “Edge City,” a hybrid Western from the Ross Brothers.…