reset-db cli command?

[JAForbes]

Resetting the db naively will confuse pgmg, as roles will still exist in the cluster. So if you want to drop the db and re-run everything (say for tests) any create role command will fail because the role already exists.

I don't want to encourage wrapping these cluster level commands in a try catch. So maybe we provide a reset-db command that drops the application db, but then re-seeds the cluster pgmg records before running the migration.

Something to dogfood.