Basic implementation of the capi-core component

[thobens]

This PR provides the initial implementation of the capi-core component. It utilizes kustomize to build the manifests from the upstream provider repository and then substitutes variables on the generated output. It does so using https://github.com/a8m/envsubst, which will be included in the commodore image used for CI/CD. This simulates the behavior of clusterctl so we can use project syn to set up CAPI.

See also:

• PR to add envsubst dependency to commodore image: Add envsubst dependency to commodore image commodore#1419

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[github-actions]

🚀 This PR has been released as v0.1.0

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[simu]

In what world is this PR documentation?