Photo Illustration by Luis G. Rendon/The Daily Beast/ClaimsConferenceIt can’t have been easy for Holocaust survivor Herbert Rubinstein to read aloud the words that a Holocaust denier posted online. “We have all been cheated, lied to, and exploited,” the post says. “The Holocaust did NOT happen the way it is written in our history books.” In no uncertain terms, Rubinstein sets the record straight. “That is a lie,” he says.Ahead of Holocaust Remembrance Day on May 6, several survivors are taking p