v0.7.0: removed cost from potion and dart tipping recipes

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/items/potions/Potion.java

@@ -452,7 +452,7 @@ public class Potion extends Item {
 		
 		@Override
 		public int cost(ArrayList<Item> ingredients) {
-			return 1;
+			return 0;
 		}
 		
 		@Override

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/items/weapon/missiles/darts/TippedDart.java

@@ -137,7 +137,7 @@ public abstract class TippedDart extends Dart {
 		
 		@Override
 		public int cost(ArrayList<Item> ingredients) {
-			return 2;
+			return 0;
 		}
 		
 		@Override