Do a proper project search for archive files.

This ensures that when we navigate into an entry of a JDK's src.zip we properly
locate the owning JDK project and everything gets wired up correctly. We'll
need to do the same for Maven artifact projects.
Debug logging when we hibernate.

Dependency references don't seem to be doing the right thing presently. I'm
seeing dependents hibernate too soon and then spurious releases. This'll help
to track that down.