This year, the Tennessee Stage Company is celebrating the 25th anniversary of its New Play Festival. The festival includes the world premiere of a play called “Raft”, about two friends, Morgan and Hedgehog, who are stranded in the Pacific Ocean on a half-deflated bouncy-castle after being washed away from a birthday beach party during a storm. WUOT’s Chrissy Keuper spoke with Tennessee playwrights playwrights Harrison Young and Carolyn Thomas about how the play evolved…