fix fastAI ImageItemList that became ImageList

ColorizeTrainingArtistic.ipynb

@@ -140,7 +140,7 @@
    "outputs": [],
    "source": [
     "if not path_lr.exists():\n",
-    "    il = ImageItemList.from_folder(path_hr)\n",
+    "    il = ImageList.from_folder(path_hr)\n",
     "    parallel(create_training_images, il.items)"
    ]
   },

ColorizeTrainingStable.ipynb

@@ -140,7 +140,7 @@
    "outputs": [],
    "source": [
     "if not path_lr.exists():\n",
-    "    il = ImageItemList.from_folder(path_hr)\n",
+    "    il = ImageList.from_folder(path_hr)\n",
     "    parallel(create_training_images, il.items)"
    ]
   },