U.S. actor and producer Robert De Niro said on Saturday that U.S. Republican presidential candidate Donald Trump should not run for president because he was "totally nuts". Trump, a billionaire businessman seeking his first public office, has courted controversy with a string of inflammatory statements about his main opponent Hillary Clinton, guns, Mexicans, Muslims and war veterans, among others. De Niro made the comments to a Sarajevo audience as he presented a digital version of Martin Scorsese's film "Taxi Driver", in which he starred, to mark its 40th anniversary. "I don't know, it's crazy that people like Donald Trump ...,...