Dev notes - How stuff works
Fedora identifiers
The UUID show on a fedora page is internal and therefore meaningless to us. Ignore it!
File visibility / permissions
hydra-access-controls is a gem embedded within hydra-head.
when you set visibility on a file, it creates 'read' and 'write' permissions objects corresponding to individuals (and / or groups thereof??). The permissions object is persisted in fedora and linked back to the file via the 'accessTo' predicate. It is therefore not a property on the generic_file object itself.