There are few who do not quietly dread a long international flight. Time stretches on, movies make less sense, sleep gets more and more elusive. Worst of all, the food tastes like prettified mud. Qatar Airways &mdash with more than eighty per cent of its revenue coming from transit passengers through Doha &mdash seems to know this better than others. They have been attacking the long-flight demons with one underlying philosophy make the passenger forget they&rsquore in the air.