Automatic merge from submit-queue (batch tested with PRs 55637, 57461, 60268, 60290, 60210). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

deprecate --show-all

`--show-all` is a pod-only filter that only affects human-readable printing of pods and only from `kubectl get`.  It hides pods which are in a terminal state.  Even at the beginning this was questionable, since you often (usually?) want to see the pods that have failed: all happy pods are alike, but every unhappy pod is unhappy in its own way.  In addition, it only worked on human-readable printers.  Doing a `-o name` or `-o yaml` showed a different set of results!

Per the mailing list discussion here: https://groups.google.com/forum/#!topic/kubernetes-sig-cli/0SxgDxObxD0

```release-note
`--show-all` (which only affected pods and only for human readable/non-API printers) is now defaulted to true and deprecated.  It will be inert in 1.11 and removed in a future release.
```

/assign @adohe 
/assign @pwittrock 
/assign @soltysh 

@kubernetes/sig-cli-maintainers