update kustomize install instructions
3. Install [KIND][kind]
- `GO111MODULE="on" go get sigs.k8s.io/kind@v0.12.0`.
4. Install [Kustomize][kustomize]
- - `brew install kustomize` on macOS.
- - `choco install kustomize` on Windows.
- - [install instructions][kustomizelinux] on Linux
+ - [install instructions](https://kubectl.docs.kubernetes.io/installation/kustomize/)
5. Install [envsubst][envsubst]
6. Install make.
7. Install direnv
