Chris Willman Music WriterEmmy-winning television producer Lena Waithe (“Twenties,” “Boomerang,” “The Chi”) is taking a big step into the music sphere, partnering with Def Jam Recordings to start up a new label, Hillman Grad Records, with the goal of what Def Jam describes as “leveraging opportunities across music, TV and film… to capitalize on the cultural significance generated when these worlds meaningfully intersect.”Although no artists signings were announced as part of the public launch