Add the CSIMigration API

[xmudrii]

What this PR does / why we need it:

Extend the v1beta1 CloudProvider-specific structs to include fields for controlling CSIMigration. For most providers, there are two fields:

• CSIMigration - used to enable CSIMigration and CSIMigration{Provider} feature gates on all relevant components
• CSIMigrationComplete - used to enable the appropriate CSIMigration{Provider}Complete feature gate. Requires CSIMigration to be enabled. This feature flag disables fallback to in-tree volume plugins and should be enabled only after deploying CSI driver to all nodes and ensuring it works correctly.

This PR includes only the API. The logic that enables the feature gates will be done in a follow-up.

/hold
Validation is missing

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Releavant to #616

Does this PR introduce a user-facing change?:

Add API fields used to enable the CSIMigration

/assign @kron4eg
/kind api-change

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: xmudrii

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [xmudrii]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[kubermatic-bot]

LGTM label has been added.

Git tree hash: b87f43a22096b44e8e5ca4af558e11aac7481131

[kubermatic-bot]

New changes are detected. LGTM label has been removed.

[xmudrii]

/retest

[xmudrii]

We've discussed internally and decided to rework the API to be a bit more user-friendly, as well as, easier to implement and maintain. I'm going to close this PR and create a new one once the new API is ready.

The issue with the CloudProvider field being overridden if Terraform is used has been moved to and merged as part of #1108.

/close

[kubermatic-bot]

@xmudrii: Closed this PR.

In response to this:

We've discussed internally and decided to rework the API to be a bit more user-friendly, as well as, easier to implement and maintain. I'm going to close this PR and create a new one once the new API is ready.

The issue with the CloudProvider field being overridden if Terraform is used has been moved to and merged as part of #1108.

/close

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.