ResNet: match implementation with Nvidia and PyTorch (#770)

* Match ResNet implementation with pytorch and nvidia

* Reduce number of Epochs

examples/train_resnet.py

@@ -36,7 +36,7 @@ if __name__ == "__main__":
     lambda x: x / 255.0,
     lambda x: np.tile(np.expand_dims(x, 1), (1, 3, 1, 1)).astype(np.float32),
   ])
-  for _ in range(10):
+  for _ in range(5):
     optimizer = optim.SGD(optim.get_parameters(model), lr=lr, momentum=0.9)
     train(model, X_train, Y_train, optimizer, 100, BS=32, transform=transform)
     evaluate(model, X_test, Y_test, num_classes=classes, transform=transform)