Make init script run on docker postgres container startup

[iFialAtFail]

Right now we have an init.sql file that creates the schema and generates some test data into the table, and that file has to be ran manually.

We should make the file run when the the container starts. The init.sql script likely needs to be adjusted, and the actual running of the script might need to be "smart" and first check to make sure the schema/tables haven't been created yet before trying to apply them