Re-implement meta-package functionality to auto-deploy pipelines

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Description

As a pipelines developer, I want the pipeline specifications that are accepted into the pipelines repo to be built and automatically deployed to all subscriber AIS nodes, so new pipelines are deployed consistently across the network in a timely manner (i.e. not waiting on sys admins).

Acceptance Criteria

• 1. When a release happens, all pipelines that have had their version incremented are built into new XNAT-ready container images
• 2. Build a "metapackage" image that can be run on loop as part of a server-side k8s deployment and update the installed pipelines to the latest versions in a target XNAT instance if they are not present
• 3. A configuration file should be able to filter which pipelines should be installed, e.g. mri.human.neuro.*
• 4. The configuration file should also be able to specify whether pipelines are automatically enabled or require system administrator approval.