For second stage use https://github.com/GoogleCloudPlatform/distroless which provides a minimal image with CA certificates.
Binary is compiled with CGO_ENABLED=0 to prevent dynamical linking to any libraries.
By dropping vendor & bindata.go from git unsee is no longer go installable, and realistically it won't be, because the build pipeline is big and involves multiple tools.
Let's just use make targets we use for development when building docker image.
Current image uses Go 1.7.5, there was an issue with haml templates preventing us from using 1.8 but it was fixed, so we should switch to latest Go version
