govc - support supervisor services creation

[rikatz]

Is your feature request related to a problem? Please describe.
govc supports partially the WCP API to manage namespaces. It needs some support for the recently added supervisor services as well, allowing VC Admins to publish a new cluster service (operator) and deploy them

Describe the solution you'd like
Add a new govc.service.* subset of commands to support creating new supervisor services.

Describe alternatives you've considered
Using dcli or vcui for this

Additional context
This issue does not cover yet deploying a version of a service to a cluster

[github-actions]

Howdy 🖐   rikatz ! Thank you for your interest in this project. We value your feedback and will respond soon.

If you want to contribute to this project, please make yourself familiar with the CONTRIBUTION guidelines.

[dougm]

Added in #2668 , thanks again @rikatz