Added a temporary ranking of the players who did the most damage for each type of mob. You can choose to enable it in the config in the kill-announce section for each type of mob by setting the ranking-message-template (more info in the new config). You can also choose how many players to show in the ranking by setting the top-ranking-players property.
To update, you should regenerate your config.yml so delete it (save it if you need to copy some text) and restart the server to regenerate it.