JOHANNESBURG (AP) — The world is celebrating Nelson Mandela Day with acts of community service and messages of goodwill to the former South African president who remains hospitalized on his 95th birthday. Here are some of the international events: UNITED NATIONS: The U.N. hosted an informal General Assembly in honor of Mandela which was addressed by former United States President Bill Clinton and co-prisoner and Mandela friend Andrew Mlangeni. U.N. staff also helped to rebuild homes in Long Island destroyed by Hurricane Sandy. WASHINGTON: The Congressional Black Caucus celebrated the life and legacy of Mandela at the Emancipation Hall in...