Service creation failed to use external network host

Suggested Release note: N/A (fixed in same version)

In the wake of JVMCBC-1527 and JVMCBC-1541, Node.addService ended up accidentally using the host from the default network to create services, regardless of which network was actually selected.

To resolve the issue, `NodeIdentifier` now has an additional property: `hostForNetworkConnections`. This is populated when the cluster topology is parsed, and always refers to the host on the selected network.