Updated openstack/openstack
Project: openstack/nova  c49544a0b049162522b981f0eed41a69f3827737

ec2: Convert to use EC2InstanceMapping object

Update the EC2 code to make use of the EC2InstanceMapping object instead
of using the db API directly for managing instance UUID to EC2 ID
mappings.

Change-Id: I66d60a29f0d909edd381e8492a4754bdd0eb8e52