WIP trying to setup dependency injection

Mirador_backend/app.py

Mirador_backend/models.py

Mirador_backend/resources/base.py

Mirador_backend/tests/tester.py

Mirador_backend/utils/app.py

Mirador_backend/utils/config.py

Mirador_backend/utils/containers.py

Mirador_backend/utils/database.py

setup.py