Add disk and memory percent_used

[kasbert]

Add percentage of disk and memory usage based on the values in disk/bytes_used and memory/bytes_used .

Includes stackdriver configuration with "custom.googleapis.com" as it is not possible to add metrics to "compute.googleapis.com".

Previous PR 824 had a wrong committer.

[k8s-ci-robot]

Hi @kasbert. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[hakman]

/ok-to-test

[hakman]

/lgtm /cc @MartinForReal @mmiranda96 /assign @dchen1107 @vteratipally

[MartinForReal]

/lgtm

[kasbert]

/retest-required

[kasbert]

/retest

[hakman]

@kasbert Seems unrelated:

Oct 31 04:03:58 systemd[1]: Started Node problem detector.
 node-problem-detector[723]: /home/kubernetes/bin/node-problem-detector: /lib64/libc.so.6: version `GLIBC_2.34' not found (required by /home/kubernetes/bin/node-problem-detector)
Oct 31 04:03:58 systemd[1]: node-problem-detector.service: Main process exited, code=exited, status=1/FAILURE
Oct 31 04:03:58 systemd[1]: node-problem-detector.service: Failed with result 'exit-code'.
Oct 31 04:04:08 systemd[1]: node-problem-detector.service: Scheduled restart job, restart counter is at 1.
Oct 31 04:04:08 systemd[1]: Stopped Node problem detector.

[hakman]

/retest

[vteratipally]

/lgtm /approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hakman, kasbert, MartinForReal, mmiranda96, vteratipally

The full list of commands accepted by this bot can be found here.

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/kubernetes/node-problem-detector/blob/master/OWNERS)~~ [vteratipally] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment