Reduces load time off testdata flight number 39 from ~400 ms to ~50 ms.

I have reduced the general Time-To-Delete (TTL) for the cache from 7 days to 3 days to prevent any pile up.

A 3h flight is roughly 60 kB, so if we expect some 180h (60 flights) to be looked at within the 3 days timeframe of the TTL this would result in a cache size of 3,1 MB for these flights.