KATE HOLTON TWO people smugglers have been found guilty of the manslaughter of 39 Vietnamese men, women and children who suffocated to death in the back of a refrigerated truck in October last year as they tried to make their way to Britain. The discovery of so many dead people - some as young as 15 - shocked Britain and Vietnam, and shone a spotlight on the illicit global trade that sends the poor of Asia, Africa and the Middle East on perilous journeys to the West. As oxygen levels fell in the back of the truck, some tried desperately…