feat: add whitelist functionality to Game.ini

- Added WhitelistIDs for server whitelisting
- Set bServerWhitelist to false by default

ti/Game.ini

@@ -1,7 +1,8 @@
 [/script/theisle.tigamestatebase]
 AdminsSteamIDs=ADMINID
 AdminsSteamIDs=ADMINID
-AdminsSteamIDs=ADMINID
+WhitelistIDs=71231XXXXXXXXXXXX
+WhitelistIDs=71231XXXXXXXXXXXX
 
 [/Script/TheIsle.TIGameSession]
 bAllowReplay=true
@@ -15,4 +16,5 @@ QueuePort=9998
 RconPassword=ADMINPASSWORD
 RconPort=9999
 ServerName=SERVERNAME
-ServerPassword=MyPassword
+ServerPassword=MyPassword
+bServerWhitelist=false