don't create *derived* nodes in nodeToIP
don't create *derived* nodes in nodeToIP

IP nodes are children of the "proper" topology nodes, not the other
way round. The former relationship is established in ipToNode.

kinvolk/scope,alban/scope,alban/scope,alban/scope,weaveworks/scope,weaveworks/scope,weaveworks/scope,weaveworks/scope,kinvolk/scope,alban/scope,kinvolk/scope,alban/scope,kinvolk/scope,kinvolk/scope,alban/scope,weaveworks/scope,weaveworks/scope,kinvolk/scope