Glance Tenant-Specific Storage Locations in Swift not documented

From the blueprint:
https://blueprints.launchpad.net/glance/+spec/swift-tenant-specific-storage

As noted in:

http://bcwaldon.cc/2012/08/20/openstack-folsom-glance-overview.html

Glance Tenant-Specific Storage Locations in Swift

The ability to store image data in the image owner-specific locations has always been an interesting feature on our backlog as storing all users' images in a single account is a no-go for some deployers. We ended up with a solution that is only implemented for Swift, but done in such a way that we can expand it easily during Grizzly.

The implementation adds a couple of configuration options:

    swift_store_multi_tenant: this must be set to 'True' to enable this feature (it defaults to 'False').
    swift_store_admin_tenants: this is a list of tenants, referenced by id, that should be granted read and write access to all swift containers created by Glance.

Assuming you configured 'swift' as your default_store and you enable this feature as described above, images will be stored in a swift endpoint pulled from the authenticated user's service_catalog. The created image data will only be accessible through Glance by the tenant that owns it and any tenants defined in swift_store_admin_tenants that are identified as having admin-level accounts.

This is missing from the docs, add it.