Seperate packet interception into seperate interface/package to get it out of controller.

[paulgmiller]

Described alot more of intent in #121

Very much a "lets see if this makes sense" rather than "please review for merging" PR.

[k8s-ci-robot]

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[k8s-ci-robot]

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[aojea]

I see you found a lot of cleanups, can you please split those commits and send in a different PR ... the Interface looks pretty neat, seems a good idea