Overview: Headlines for April 20, 2016; Battle for New York: Clinton & Trump Win as NYC Voters Report Chaos & 'Irregularities' at the Polls; New York Primary: Chaos at Polling Sites, Broken Scanners & Whole Blocks Purged from Voter Rolls; Is the U.S. Backing Rousseff's Ouster in Brazil Opposition Holds Talks in D.C. as Obama Stays Quiet