Make naming bit more consistent

Author: Andre601

core/src/main/java/ch/andre601/advancedserverlist/core/profiles/replacer/placeholders/PlayerPlaceholders.java

@@ -44,7 +44,7 @@ public PlayerPlaceholders(GenericPlayer<?> player){
         if(player.getPlayer() == null)
             return;
 
-        this.replacements.put("${player playedBefore}", player.hasPlayedBefore());
+        this.replacements.put("${player hasPlayedBefore}", player.hasPlayedBefore());
         this.replacements.put("${player isBanned}", player.isBanned());
         this.replacements.put("${player isWhitelisted}", player.isWhitelisted());
         this.replacements.put("${player uuid}", player.getUniqueId());