Monitoring API: Add KubeStateMetrics api

[marioferh]

after: #2322

[openshift-ci]

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[openshift-ci]

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This pull-request has been approved by: marioferh
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[marioferh]

/retest-required

[openshift-ci]

@marioferh: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-aws-serial-techpreview-2of2	1b8a123	link	true	/test e2e-aws-serial-techpreview-2of2
ci/prow/verify-crd-schema	1b8a123	link	true	/test verify-crd-schema

Full PR test history. Your PR dashboard.

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