
Since https://review.openstack.org/#/c/163462/ and https://review.openstack.org/#/c/162649/4 in gnocchi, all kind of aggregations have been moved in the same URI namespace (/v1/aggregation/...) and we can use complex query to make aggregation across multiples metrics. This change sync the ceilometer alarm API and Rules to match these changes. Change-Id: I015af585595e6880b527161fe5c8b34eeb7bfe29