Allow ip resolver to know for which vm other vm is being resolved

Such feature is needed, in case we would like to resolve ip addresses in different way depending which node resolves other nodes.

##### Sample use case

When setting up cluster across different regions (in EC2 or eucalyptus) we would like to resolve nodes within the same region by private ip, and nodes that are in different region by public ip and therefore we need information which node is resolving which one.