Password protection for database and broker

[uniqueg]

Is your feature request related to a problem? Please describe.
MongoDB and RabbitMQ are currently unprotected or protected by default credentials.

Describe the solution you'd like
For a start, use config settings to hold default credentials. Once a strategy for passing secrets during build time (see #64) is in place, remove credentials from config and pass securely.

Describe alternatives you've considered
N/A

Additional context
N/A

[uniqueg]

This has already been done for the database. See #64 for details