Tooling to generate OLM metadata

[aliok]

Metadata published to OperatorHub (see #68) is initially created manually.

For future versions, we can generate the OLM metadata using the manually created one.

Required:

• Tooling itself
• Documentation

[aliok]

/assign @aliok

[aliok]

We can use Operator SDK cli to generate CSV also for non-Operator-SDK operators.

I've done some experiments here: https://github.com/aliok/eventing-operator/tree/olm-experiments-bundle

Filed 2 tickets:

1. operator-name in csv-config.yaml is ignored operator-framework/operator-sdk#2266
2. gen-csv should find out the latest CSV version operator-framework/operator-sdk#2267

and objected operator-framework/operator-sdk#2249 which makes Operator SDK cli unusable for upstream Knative eventing operator.

Gonna leave it there until Operator SDK team makes a decision.

I don't think we need to pursue any other tool. We just need to give Operator SDK team good feedback to help them support what we need.

[aliok]

Update:
I am still helping Operator SDK team to make the CLI supporting the cases we need at Knative operators: operator-framework/operator-sdk#2511

We're very close to have tooling ready for our cases.

[aliok]

operator-framework/operator-sdk#2511 has lots of progress.
Once that PR is merged and we fix #128, we can use operator-sdk as is to generate OLM metadata.