3.x: TokenAwarePolicy invesigate down replica flow

[dkropachev]

There is following code:

java-driver/driver-core/src/main/java/com/datastax/driver/core/policies/TokenAwarePolicy.java

Lines 222 to 231 in e2367be

	if (host.isUp()
	&& replicas.contains(host)
	&& childPolicy.distance(host) == HostDistance.LOCAL) {
	// UP replicas should be prioritized, retaining order from childPolicy
	return host;
	} else {
	// save for later
	if (nonReplicas == null) nonReplicas = new ArrayList<Host>();
	nonReplicas.add(host);
	}

That treats down replicas same way as nonreplicas, it looks wrong, we need to look at it.