MIAMI (Reuters) - Business maverick Sir Freddie Laker, who built an airline empire on low-cost international travel only to see it collapse in ruins, has died in Miami, a family source said. The source, a business partner of Laker's son who asked not to be identified by name, said the 83-year-old Laker died early on Thursday of undisclosed causes. In the 1970s, Laker Airways' cut-price Skytrain service from Britain to the United States opened new vistas for millions of tourists who had previously regarded air travel as a preserve of the rich. Skytrain, which opened in 1977 offering a one-way...