Cli clean-ups

This page is a capture in the next bucket of the product backlog — a pre-sprint idea, not yet pulled into a sprint as a story.

• we still seem to support --entity currencies. This should now be invalid. Done.
• we are still exporting as JSON. We should instead allow CSV and XML exports only.
• add recipes for all commands.
• should be able to list all admin accounts.
• list command should support table output.
• is admin should be a bool: --is-admin arg (=0)
• add account duplicates logic. We should have a single service for this.
• split application into entities.