Create sample second flyway process for core data model work

[wbprice]

Minimal amount of work to get a second flyway container running locally that only looks at core data model migrations

Does not address running a second flyway process in AWS or update the flyway container to pack in core data model migrations.

Note: This puts the flyway schema history table for the core data model under a "cdm" schema for convenience (it wasn't immediately obvious how to put two different flyway schema history tables on public and this works)

Usage:

docker compose up from npd root directory will run a new cmd-migrations service, which creates a cdm schema, a flyway schema history table, and an address table. The contents of cdm/migrations/V1__create_initial_schema.sql are throwaway, do whatever you want with that.

[rmillergv]

great starting point, thanks!