Support for SQLite

Is your feature request related to a problem? Please describe. Testing requires PostgreSQL which makes it harder to run the test than required.

Describe the solution you'd like Support SQLite as a database backend for small deployments and testing. We would need new environment variables to control the database backend. As part of the we should prefix the variables e.g. POSTGRE_HOST, POSTGRE_DB, etc.

Additional context See exposed configuration for sqlite here.