added Chinese Traditional translation

resources/lang/zh-TW/items.php

@@ -0,0 +1,10 @@
+<?php
+
+return [
+
+    'quantities'            => '數量 | 數量',
+    'sales_price'           => '定價',
+    'purchase_price'        => '售價',
+    'sku'                   => '庫存',
+
+];