[release-0.4] Add prereq, install page, upgrade

[k8s-infra-cherrypick-robot]

This is an automated cherry-pick of #1088

/assign shivamerla

[shivamerla]

/assign @a-mccarthy

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[shivamerla]

/release-note-none

[shivamerla]

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

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Git tree hash: f540fa24b290d6a6e888fab2d3fc58a9a99a6acc

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: k8s-infra-cherrypick-robot, shivamerla

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