Updates the swift store to support multiple tenants:
* Added configuration option for swift_store_multi_tenant.
* Updated the swift connection creation logic so that in multi-tenant
mode the token and storage URL from the service catalog are used
to create swift connection.
* When in multi-tenant mode locations URL's (stored in the DB) do
not contain hard coded swift credentials.
Includes unit tests to verify multi-tenant swift storage URLs.
Partially implements blueprint: swift-tenant-specific-storage.
Change-Id: I45fc97027e6f211ac353513c2d9d6da51ccf4489
8b2d038185