Enhance the `run db` command
Enhance the `run db` command

This makes the command much more flexible and also adds
a few new features such as being able to run any psql
command or list all databases.

nickjj/build-a-saas-app-with-flask,nickjj/build-a-saas-app-with-flask,nickjj/build-a-saas-app-with-flask,z123/build-a-saas-app-with-flask,nickjj/build-a-saas-app-with-flask,z123/build-a-saas-app-with-flask,z123/build-a-saas-app-with-flask