[WIP] Jobs

@cjh1 in case you want to keep an eye on this, this PR adds

- A general purpose data model and REST API for batch job management
- Scoped token support, including supporting authorization for clients that do not have a corresponding user document.
- Making `ModelImporter.model` a static method so that it can be called more easily outside of objects that have ModelImported mixed in.
True, maybe we could allow an additional "extra settings" field that they could edit as JSON.

This is also just for the client side of the application. The workers will have their own config files they will use.