The woman who allegedly told three Jewish kids “Hitler should have killed you all” before spitting on an 8-year-old boy in Brooklyn has been arrested, cops announced Friday. Christina Darling, 21, was arrested and charged Friday with aggravated harassment and menacing, both as hate crimes, and acting in a manner injurious to a child in connection to the Jan. 14 incident, NYPD Hate Crimes said . Darling stormed up to the boy, who was with two other kids around 12:30 p.m. on Avenue P near Coleman Street in Marine Park, about five blocks from her home, police said. She snarled...