CNBC update: US-Cuba sign aviation pact

CNBC's Sharon Epperson reports the U.S. and Cuba have signed an aviation pact; China warns the U.S. there would be serious consequences to naming a plaza in front of the Chinese embassy in Washington after a pro-democracy dissident and Nobel Peace Prize winner; and former UN Secretary General Boutros Boutros-Ghali has died, reports CNBC's Sharon Epperson.