Greek PM Tsipras Resigns, Calls for New Election as Left Wing of Syriza Splits to Form New Party; Sen. Bernie Sanders: From Greece to Puerto Rico, the Financial Rules Are Rigged to Favor the 1%; Global Warming Worsens California Drought as July Becomes Hottest Month on Record; In Victory for Corporations, Court Rejects Rule on Labeling Goods Containing “Conflict Minerals”; In a Final Speech, Civil Rights Icon Julian Bond Declares: “We Must Practice Dissent.”