Per request, I created a way for the whitelist to be used in a mysql database. It will override permit and unpermit commands, and makes them available to be used in the console. You can also add to the whitelist directly into the mysql, and the whitelist in game will be updated when the server restarts. Comes with a default config file and translation file.
This will not include into the mysql table anything already in the whitelist. If you want them in the mysql, you need to add them into the mysql or call the command again.
If you set AddtoGameWhitelist to false, you can still use permit and unpermit to add and remove from the mysql, but it will stop adding and removing from the game whitelist. If you want to maintain a whitelist in case of future whitelisting, this is the way to go. Remember to delete the whitelist file in your server folder if you are taking off the game whitelist and you used it before.