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When I used `godep save -r ./...`, it caught that the vendored copy of codegangsta/cli wasn't using itself. This doesn't really matter since it's in codegangsta's test files, but godep is going to keep making this change when anyone runs `godep save -r` so let's get it committed now.

This does not bump the imports used in `.travis.yml` as travis does not actually work with them yet...