Former US president Barack Obama is getting a little help from his friends, including three former presidents, in celebrating the opening of his presidential museum in Chicago.The guest list for Thursday’s dedication ceremony includes Bruce Springsteen, Stevie Wonder, Christina Aguilera and Bono.Obama and former first lady Michelle Obama posed for pictures before the ceremony with former presidents Joe Biden, George W. Bush and Bill Clinton along with former first ladies Jill Biden, Laura Bush...