Upgrade kubernetes library

This depends on !753 (closed).
Though you can cherry-pick the top commits with the bottom commit from !678 (closed).
I would prefer !753 (closed) gets merged first though because maintaining that will be a horrible task.
@nolith I squashed all your commits into one to make this MR more readable but kept it separate from mine and keeping you as the author to ensure I am not taking credit for your work on this.

Why was this MR needed?

#2742 (closed) is blocked by this
#2681 (closed) is blocked by this

=== RUN   TestKubernetesBuildFail
Running with gitlab-runner dev (HEAD)
  on  ()
WARNING: Namespace is empty, therefore assuming 'default'.
Using Kubernetes namespace: default
Using Kubernetes executor with image docker:git ...
Waiting for pod default/runner--project-0-concurrent-07prl9 to be running, status is Pending
Running on runner--project-0-concurrent-07prl9 via Martell's Secret Device :P ...
Cloning repository...
Cloning into '/gitlab-org/gitlab-test'...
Checking out 6907208d as master...
Skipping Git submodules setup
$ exit 1
ERROR: Job failed (system failure): command terminated with exit code 1
--- PASS: TestKubernetesBuildFail (32.67s)
PASS
ok      gitlab.com/gitlab-org/gitlab-runner/executors/kubernetes        32.794s

Does this MR meet the acceptance criteria?

Previously there were other tests failing because the runner would give an exception when the strings did not match. I ran all the tests on a live kubernetes cluster and everything passes

• Tests
  • All builds are passing