Merge pull request swiftlang#88 from foulkesjohn/master

Updated to 4.0.2

Swift 3.1.1 release.

Errant /

Get the nightlies from jenkins :/

22 Jan snapshot.

Update Dockerfile for 3.0.2

Improved slight reordering to reduce number of layers and improve caching opportunities for images (i.e. relatively idempotent commands are up there).

Make sure curl is installed for swift-build (swiftlang#35)

Merge pull request swiftlang#33 from zwaldowski/patch-1

Use clang-3.6 as compiler on Trusty

use 2016-09-02 snapshot

 use 2016-08-30 snapshot