=pro #3015 Upload dist to S3 downloads.typesafe.com
(cherry picked from commit a6f8b5516a5a66cd4da1ad68c13f1a5c66eeb7e7)
Merge pull request #1672 from akka/wip-3015-s3-2.2-patriknw

=pro #3015 Upload dist to S3 downloads.typesafe.com (backport)