The flow is better this way, since we can introduce pods
just after seeing them in kubectl describe node.
Also, add some extra info when we curl the Kubernetes API.
This is a new thing in Kubernetes 1.14. Added some details
about it (TL,DR it helps with cluster scalability but you
don't even have to know/care about it).
1) When introducing "kubectl describe", we ask people to
look at "kubectl describe node node1", which shows
them a bunch of pods. This makes it easier to contrast
with the (empty) output of "kubectl get pods" later.
2) Then, instead of going straight to "-n kube-system",
we introduce "--all-namespaces" to show pods across
all namespaces. Of course we also mention "-n" and
we also explain when these flags can be used.
3) Finally, I rewrote the section about kube-public,
because it was misleading. It pointed at the Secret
in kube-public, but that Secret merely corresponds
to the token automatically created for the default
ServiceAccount in that namespace. Instead, it's
more relevant to look at the ConfigMap cluster-info,
which contains a kubeconfig data piece.
The last item gives us an opportunity to talk to the
API with curl, because that cluster-info ConfigMap is
a public resource.
This was discussed and agreed in #246. It will probably break a few
outstanding PRs as well as a few external links but it's for the
better good long term.
