Support RFC6902 json patches for manifests

[simplysoft]

User Story

As a user I would like to patch the manifest using RFC6902 in addition to json merge patch support introduced with #280 so that I can e.g. easily add command arguments to conainers

Detailed Description

json merge patch (RFC 7396) has the limitation that is not possible to extend lists (without having to duplicate existing elements in the patch itself) or do some more advanced patches.

The underlying evanphx/json-patch library used would already support this, but operator currently does not.
It would be great to extend support, ideally in similar way than kustomize supports different patch types, e.g.

- patch: |
    - op: add
      path: /spec/template/spec/containers/0/args/-
      value: --additional-sync-machine-labels=topology.kubernetes.io/.*
  target:
    kind: Deployment

/kind feature

[k8s-ci-robot]

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[hjoshi123]

@simplysoft I am interested in working on this since I ran into this during my capi operator approach. Do you think I can take this up?