Add OWNERS file for dashboard

[wbuchwalter]

fix #443.

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This change is 

[coveralls]

Coverage decreased (-0.1%) to 28.486% when pulling 5ce1551 on wbuchwalter:dash-owners into d3a615d on kubeflow:master.

[coveralls]

Coverage remained the same at 28.606% when pulling fc37492 on wbuchwalter:dash-owners into d3a615d on kubeflow:master.

[jlewi]

Please remove me. I'm already a root approver and I don't have special knowledge of the Dashboard.

Also do you want to be listed as a root approver
https://github.com/kubeflow/tf-operator/blob/master/OWNERS#L13

I know you have a different role but it might make more sense to have you focus reviewing the UI
and then also kubeflow/examples

[jlewi]

Remove all of these reviewers.
Approvers shouldn't also be listed as reviewers.

None of the non-approvers listed here have special familiarity with react/javascript.
I sent a request yesterday for more people with javascript/react experience to volunteer but we'll see.

You could add @swiftdiaries as a reviewer. He's working on the central UI.

[wbuchwalter]

@jlewi per your comment:

• Added myself as a root approver.
• Added only @jimexist as an approver in the dashboard dir (since he is not root approver)
• Added @swiftdiaries as a reviewer in the dashboard dir
• Cleaned the root OWNERS file by removing the reviewers that were already approvers

[jlewi]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jlewi

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• OWNERS [jlewi]

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