README: add info about creating the test db+creds
upgrade to Korma 0.4.0 and jdbc 0.3.5

- Adapted syntax
- The moves.game_id column got renamed to moves.games_id to match the referenced table name (games)
- Removed some fields declarations because of:
https://github.com/korma/Korma/issues/251
upgrade midje to 1.6.3
refactor DDL functionality to its own file
gitignore .nrepl-port
move load-credentials to model.clj and test it