Don't join path with root for the second time (#89)

torchvision/datasets/folder.py

@@ -62,7 +62,7 @@ class ImageFolder(data.Dataset):
 
     def __getitem__(self, index):
         path, target = self.imgs[index]
-        img = self.loader(os.path.join(self.root, path))
+        img = self.loader(path)
         if self.transform is not None:
             img = self.transform(img)
         if self.target_transform is not None: