The s3 image configuration options were deprecated for removal in newton
Clint has a patch up to remove the boto dependency from nova  which
is only used in the nova.image.s3 module.
Rather than remove the boto dependency, I think we should just remove
this code. Is there any reason to not do that now that Ocata is open and
it's been over the requisite 3 month window of deprecation for CD shops?
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