importing itemized subscriptions for content-hosts and activation-keys needs to support future dated subs
When future-dated subscriptions become available in manifests, importing a CSV to mirror existing with future dated subs needs to work.
For example, a content-host has a "RHEL" sub that expires 2017-02-01. An export csv could be modified to duplicate that subscription with a new one that starts 2017-02-02. Start dates should be a column checked when making the import.