leftoverrev-index on S3 Buckets #146

when we have a fixed pair of version and revision in that case the rev-index is created when upload the package first time but it does not point to the latest iterations upon recipe changes. It let's us upload packages with different hashes but same version-revision ideally it should force us to either update the revision if we have revision or if we don't have revision force us to update version.

Upload first creates MANIFESTS/rev-index/PACKAGE/ver-rev/hash then it uploads the tar file in store/arch/11/11111111/tar.gz since the rev-index already exists it keeps pointing to the store/arch/11/11111111/tar.gz but new tars are uploaded at store/arch/22/222222/tar.gz