Updated openstack/openstack
Project: openstack/nova  d5c7b11d86ee37186a61c357f7d42db7a8aa8626

Make a flavorRef validation strict

V2.0 API doesn't allow empty string as flavorRef and it returns a
BadRequest response if receiving it.
Now V2.1 API doesn't check it now and this patch makes V2.1 API check.
In addition, this patch adds tests for checking both API behaviors.

Partially implements blueprint v2-on-v3-api

Change-Id: I6c80b66102f00c832922cb507b82e9f3b534557f