Use name property in OS::Nova::Server if set

Currently the name property is ignored if specified; the intention
was to use the name as the nova server name if specified.

This is implemented by overriding physical_resource_name
in the same way as SwiftContainer.

Change-Id: I06a6f3d69119fb470eb54930c2bd7b329cabd6c7
Closes-Bug: #1229244
Merge "Use name property in OS::Nova::Server if set"