We could just as well have done this with global `nconf`, couldn't we? And when we're not using global nconf what is the justification or use of `overrides` vs. `defaults`. It's just it seems the whole idea of removing nconf from global seems pointless, when we could just use `overrides` in the tests...

Either way, the idea of multiple config files is not unreasonable... I'm would have preferred them more declarative. But whatever...