Automatically sync Swift and HPSS namespaces

Right now, in order to keep the HPSS namespace up to date in Swift's container server databases, an included tool must be run by the administrator every so often. This isn't ideal because changes made through other HPSS client interfaces would not be picked up for quite some time, making it difficult to tell what's actually being stored. We want to have some way to automate this, so every time an object gets put into HPSS through another interface, Swift will know about it.