Make ModifierNBT an iterator over modifier entries

Saves a getter call mostly

src/main/java/slimeknights/tconstruct/library/tools/nbt/ModifierNBT.java

@@ -14,17 +14,20 @@
 import javax.annotation.Nullable;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Spliterator;
+import java.util.function.Consumer;
 import java.util.stream.Collectors;
 
 /**
  * NBT object containing all current modifiers
  */
 @EqualsAndHashCode
 @RequiredArgsConstructor
-public class ModifierNBT {
+public class ModifierNBT implements Iterable<ModifierEntry> {
 
   /** Instance containing no modifiers */
   public static final ModifierNBT EMPTY = new ModifierNBT(Collections.emptyList());
@@ -65,6 +68,24 @@ public int getLevel(ModifierId modifier) {
   }
 
 
+  /* Iterator */
+
+  @Override
+  public Iterator<ModifierEntry> iterator() {
+    return modifiers.iterator();
+  }
+
+  @Override
+  public void forEach(Consumer<? super ModifierEntry> action) {
+    modifiers.forEach(action);
+  }
+
+  @Override
+  public Spliterator<ModifierEntry> spliterator() {
+    return modifiers.spliterator();
+  }
+
+
   /* Withers */
 
   /**