[ModelSync Controller] Rename, Refactor, and Move

[jlewi]

The ModelSync Controller isn't really a model sync controller.

Its more of a generic controller aimed at building declarative APIs.

You specify a lambda that determines whether the world needs to be updated and if so what parameters are needed for a Tekton pipeline to syncronize the world.

The controller will then launch the Tekton workflow.

We will probably want to reuse this controller for a lot of our continuous delivery infrastructure.
So we should probably move it to kubeflow/testing and rename it.

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