Create app schema automatically

[snpaul22]

When running Lube Logger with a Postgres backend, Lube Logger requires you to create an app schema in the database before the program will be functional. This commit is two part:

1. Created the initialization script that will check the Postgres db for the existence of the app schema. It will create it automatically at start if it doesn't exist. It will skip and continue starting if it does exist.
2. Added a bind mount for the init.sql initialization script to the docker-entrypoint-initdb.d make the script run on container startup.