opentraveldata/optd — pull request #22 by wolfer7 (2014-01-16 18:12:39+00:00)
Title: added from_date and to_date to airline alliance membership file

I added two new columns to the alliances membership file: from_date and to_date. This allows to get the alliance membership at a given date. There are still some airlines and dates missing, but I plan to do some more updates once we agreed on the file layout.