Release note gathering

To generate a release note for the release v0.9.8-rc.1 in Markdown:

The pre-requisite is to run go get several times to install dependencies:

$ go get -u "github.com/google/go-github/github"
$ go get -u "golang.org/x/oauth2"
$ go get -u "golang.org/x/context"

For a release note for a release-candidate version of kube-aws, run:

$ VERSION=v0.9.8-rc.1 go run relnotes.go

For one for a final version, run:

$ VERSION=v0.9.8 go run relnotes.go