Overview: Headlines for July 27, 2016; 'Biggest Crack in Glass Ceiling Yet': Clinton Becomes First Female Major-Party Presidential Nominee; Hundreds of Sanders Delegates Walk Off Convention Floor in Protest of 'Rigged' Election; 'It's a Bittersweet Time': Some Sanders Backers Stay Inside DNC, Now Plan to Support Hillary Clinton; Danny Glover & Rep. Luis Gutiérrez on Sanders, Clinton and the Long Arc of U.S. Movements; Watch the Full DNC Speeches of the Mothers of Sandra Bland, Jordan Davis, Trayvon Martin; Danny Glover & Bernie Delegate Larry Hamm: The Sanders Movement Must Stay Mobilized to Push Change; Mumia Abu-Jamal Calls from Prison to Comment on DNC, Black Lives Matter and Mass Incarceration