Conversion of simulation database

Initially, we developed the simulation database using an SQLite database backend. This has resulted in (relatively) easy development of the simulation database and query functions to demonstrate how to interrogate the database after creation. To align with organisational norms, a PostGRES database backend is preferred.

The task is to generalise the existing sqlite database code using a database abstraction layer (e.g. SQLAlchemy), so we can then use any database of our choice.