This tags new images every commit (via Travis) as latest, and every tag gets pushed as a separate tag as well.
This adds `verify-gofmt` and `gofmt` make targets for quick go-fmting. It also adds a `verify` target which verifies `gofmt` and the runs the unit tests. Travis now runs `make verify` instead of just `make test` as the tests.
This commit sets up Travis CI to run the unit tests. It installs glide, initializes the vendor directory, and then runs `make test`.
