By ED WHITE Contributing Writer CHICAGO (AP) – A 21-year-old man has been charged with a hate crime, arson and other offenses for a cross that was set on fire in a popular downtown park, police said. Merlin Lu admitted to a TV station this week that he was responsible for the recent cross burning in Grant Park. But he insisted that he was protesting President Donald Trump and Christian nationalists and was not using the cross as a historical sym…