Added iterator capabilities to the menu class (#73)

* Added iterator capabilities to the menu class

* Replaced @return doc block with an actual return type

* Minor code style fix

src/Menu.php

@@ -2,16 +2,19 @@
 
 namespace Spatie\Menu;
 
+use ArrayIterator;
 use Countable;
+use IteratorAggregate;
 use Spatie\Menu\Html\Tag;
 use Spatie\Menu\Html\Attributes;
 use Spatie\Menu\Helpers\Reflection;
 use Spatie\Menu\Traits\Conditions as ConditionsTrait;
 use Spatie\Menu\Traits\HasTextAttributes as HasAttributesTrait;
 use Spatie\Menu\Traits\HasHtmlAttributes as HasHtmlAttributesTrait;
 use Spatie\Menu\Traits\HasParentAttributes as HasParentAttributesTrait;
+use Traversable;
 
-class Menu implements Item, Countable, HasHtmlAttributes, HasParentAttributes
+class Menu implements Item, Countable, HasHtmlAttributes, HasParentAttributes, IteratorAggregate
 {
     use HasHtmlAttributesTrait, HasParentAttributesTrait, ConditionsTrait, HasAttributesTrait;
 
@@ -721,4 +724,9 @@ public function __toString(): string
     {
         return $this->render();
     }
+
+    public function getIterator(): Traversable
+    {
+        return new ArrayIterator($this->items);
+    }
 }