FRANKFURT (Reuters) - Qatar Airways is considering taking a stake in Germany's Lufthansa , its chief executive Akbar al-Baker was quoted as saying by German news agency dpa."If there is an opportunity to invest in Lufthansa, we would like to do it," Akbar Al-Baker told dpa in Doha on Sunday on the sidelines of a visit of the premier of regional state Lower Saxony, Stephan Weil, to Qatar.Initially, Qatar Airways would also look into a partnership with Lufthansa, Al-Baker was quoted as saying...