Have you ever wondered what Canadian singer-songwriter Shawn Mendes contractually requires before he takes the stage? One Texas university doesn’t want you to know.The University of Texas at El Paso is requesting to withhold the "Stitches" singer’s contracts for an October performance at the university, a lawsuit filed in Travis County says.Mendes, who sang with Miley Cyrus at this year’s Grammy Awards, performed at the West Texas university on Oct.