WIP: always call update{ServiceNodes,ExitNodes}

[jcorbin]

Unsure if this, or a less heavy handed change is necessary to get parital
affinity working.

[Raynos]

I think this is needed, but we should keep an eye on it. Can we add a custom logline here so we can see how often this happens.

This should be fine except for the CPU runaway case :(

[jcorbin]

Aye, stats on changes and updates would be great, will add.

Currently the only affect of updateServiceNodes is under the partial affinity feature, so noop until then.