List requested Availability Zones

Currently server show and server list –long output, displays the current AZ of the instance. That is, the AZ to which the host of the instance belongs. There is no way to tell from this information that whether the instance create request included an AZ or not.

This implementation enables users to validate that their request for Availability Zone was correctly processed and satisfied, by returning back information, not only about current placement of the instance, but also original request.