(FDA sought permanent injunction that would bar defendant from selling unpasteurized milk products in interstate commerce and from introducing into interstate commerce food that is "misbranded"; advocate of raw milk sought to intervene in case on behalf of not-for-profit “Right to Choose Healthy Food” organization and other private citizen’s clubs and “similarly gastronomically-inclined” individuals; court denied advocate’s intervention; advocate was not a licensed attorney and was attempting to protect the legal rights of the above-named individuals; advocate did not have legally cognizable interest in action sufficient to establish intervention as of right; permissive intervention also denied by court because it would cause delay).