A zone export request does not include pool/zone attributes. That's why zone import requests neither contain it. As the end user might want to import their zones to a pool that will match the same criteria as the old pool, this ticket should add an option to specify designate zone_attributes on zone import via 'X-Designate-Zone-Attributes' header.

So when a header is given along with zone import request, the zone should receive the 'zone_attributes' attribute exactly as it happens during new zone creation with 'zone_attributes' given in json attributes.