Organizers of Outside the Box, the free performing arts festival founded by philanthropist Ted Cutler, have added another act. Lea DeLaria, who plays Carrie “Big Boo’’ Black in the Netflix hit “Orange Is the New Black,’’ will headline the festival’s Tremont Tent. DeLaria (right), who was the first openly gay comic on television, is a talented vocalist whose new CD is called “House of David: delaria + bowie = jazz.’’ Outside the Box is set to take place on Boston Common July 13-17. Previously announced acts include Smash Mouth, Daughtry, the Young Wild, the Wild Feathers, the Record Company, and Michael Franti & Spearhead. For more information, visit www.otbboston.com.