Setup TTL for HTTP connections

[alexkorotkikh]

Pooled HTTP connections cache resolved DNS records. That doesn't work correctly with ELB and traffic switches: even thought all the traffic was switched to a newer stack, persisted connections are still working with the one they've cached. To avoid this situation, HTTP connections should have TTL.

Some more info: https://stackoverflow.com/questions/29107681/httpclients-poolinghttpclientconnectionmanager-and-dns-caching