Flying high? Barclays is out with a positive note on the airline sector, saying stocks could rise 20% on a mix of higher fares and lower jet fuel prices. Investors should also keep an eye on the merger front. With all signs pointing to an eventual marriage between American Airlines and US Airways, future industry consolidation/partnerships could still be on tap. A particular focus will be on Washington DC to see if rules governing foreign ownership of U.S. carriers are relaxed.