There’s no question that Rose Fitzgerald Kennedy was the matriarch of one of the most famous families that Cape Cod and the United States has ever had. So when two of her grandsons paid a visit to the John F. Kennedy Museum in Hyannis last year, it only reinforced the powerful image of the philanthropist and socialite known for her love of “family, faith, and public service.” “Last year, there were two speaker events,” recalled John Allen, executive director of the JFK Museum