charlie currently has the root directory /srv/deployment-charts/helmfile.d/services as a module-level constant, meaning it's only usable on wikikube. We should make that configurable via command-line flag so that it can be used in other clusters too.
As a side effect, that will also mean it can be used from e.g. /home/elitehacker/my-local-checkouts/deployment-charts/helmfile.d/services. That's exactly as error-prone, but exactly as powerful in certain situations, as running helmfile apply in the same way, so (this being a power tool for power users) we ought to support it.