Software template for ArgoCD

[davgordo]

As an Assemble contributor or demo'er I want an ArgoCD software template So that I can spin a ArgoCD instance to use for continuous delivery

Acceptance:

• Automatically provision operator
• Automatically provision instance
• Automatically provision service accounts / RBAC

[malacourse]

Pull request ready for review: https://github.com/halkyonio/assemble-platforms/pull/7

[marshallpowell]

@malacourse can we mark this task as DONE?