Verify the response attributes of 'update-aggregate' API

This patch verifies the response attributes of 'update-aggregate'.
The response body of v2 and v3 API has the same format:
{
    "aggregate": {
        "availability_zone": "nova2",
        "created_at": "2013-08-18T12:17:56.259751",
        "deleted": false,
        "deleted_at": null,
        "hosts": [],
        "id": 1,
        "metadata": {
            "availability_zone": "nova2"
        },
        "name": "newname",
        "updated_at": "2013-08-18T12:17:56.286720"
    }
}
This patch also fixes a typo bug of the schema.

Partially implements blueprint nova-api-attribute-test

Change-Id: I89547d8069aae9d2ad0b4cd081843865f42bc4e7
Verify delete server attributes of Nova API

This patch adds the JSON schema for Nova V2 & V3 delete server
API response and validate the response with added JSON schema
to block the backward incompatibility change in the future.

Response status of delete APIs is 204

Partially implements blueprint nova-api-attribute-test

Change-Id: Ibcc8d7067531f41a55c7ced93911f34e87e16f0e
Merge "Verify the response attributes of 'update-aggregate' API"
Merge "Verify delete server attributes of Nova API"