PARIS (Reuters) - Air France-KLM said slowing travel demand will hurt ticket sales in the rest of 2019, sending its shares tumbling as the airline group posted lower-than-expected quarterly earnings.Unit revenue, which tracks airline takings in relation to flight capacity, fell 0.6% in the July-September quarter and is poised to decline further, the company said on Thursday. Its stock fell as much as 11.9% before partially recovering to trade down 4.4% at 10.31 euros by 0905 GMT.The airline..