update index without upload when already in pool

[sgo]

Sometimes I want to promote a package to a different component to support staging environments. So I use the components unstable, releasecandidate and stable.
Currently I have to re-upload the package in order to install them in releasecandidate or stable but it is actually already in the pool so it would be faster if we could skip this step.

[krobertson]

I'll take a look. I know with S3 you can provide an MD5 on upload, so may be able to start doing that and compare MD5+size before uploading as a check.

[krobertson]

Added support for this in 6bb64e1 and will likely cut a new release tonight.