Now the top-level keys are: 'META' (metadata about the collection run,
so that whoever pulls this file back to boss doesn't have to check its
ctime/mtime to know how stale the data is -- times in GMT); 'info',
which has keys like 'images', 'vms', 'networks', 'subnets', 'ports',
'routers', and a UUID->dict where the dict has a 'name' field (HRN),
'status' (if the resource has status; all do); and 'deleted' (True
or False).  Then the periods (which were previously top-level keys)
are now keys in the 'periods' top-level dict.