Fix Shell services test

Do not override environment variable in ubuntu defaults

Jenkins: remove dead 'use server version' code

Update UI doc for the usage of Kubernetes UI

V0.21.1 merge to master

This reverts commit aa618a97.

Automated cherry pick of #10488 on upstream release 0.21

It had been removed in upstream, but had been kept by mistake here.

For symmetry with systemd

We have the workaround for Salt's problems here, but we should still express
our intent.

I don't think it actually makes a difference based on how we're using it,
but this is now more of a precise change.

This may help Salt reload services correctly, although we still
need the script until Salt's bug with reloading services on systemd
is resolved.

Salt bug: https://github.com/saltstack/salt/issues/16778

Also work around problems with Salt & systemd services, in particular
that Salt doesn't issue a daemon-reload.

Fix two issues in cherry_pick_pull.sh

* Ignore errexit in trap handler
* Check for branch (since two people have complained now..)

Add `build-official-release.sh` (take two)

Fixes #8945: Cleanup log symlinks on remove & dead log symlinks

Fix quoting issue on sed

update kubectl get outputs in examples/cluster-dns

update the output of kubectl get in examples/kubernetes-namespace

Make READMEs even more obviously versioned.

Add prometheus metrics for altTokenSource.

Fully update gcloud before Jenkins runs

Install the kubectl binary on nodes in addition to the master.

End to end test for Kibana liveness

Promote ElasticSearch test to non-flaky suite

update the kubectl get command in examples/node-selection

Automated cherry pick of #10562

Automated cherry pick of #10884 on upstream release 0.21