Adds increased scrapper cost when used excessively

src/main/java/net/knarcraft/blacksmith/formatting/BlacksmithTranslatableMessage.java

@@ -143,7 +143,12 @@ public enum BlacksmithTranslatableMessage implements TranslatableMessage {
     /**
      * The format to use for formatting any message spoken by a blacksmith NPC
      */
-    NPC_TALK_FORMAT;
+    NPC_TALK_FORMAT,
+
+    /**
+     * The text to display when explaining that a cost must be a positive double
+     */
+    DOUBLE_COST_REQUIRED;
 
     /**
      * Gets the message to display when displaying the raw value of messages