why override the default step()

[QasimWani]

https://github.com/greydanus/baby-a3c/blob/85899d76bd1a72d9e9055ed35894390802e31240/baby-a3c.py#L72-L78 Why did you override the default implementation of step(closure)? The default one calculates exponential moving average. Your implementation doesn't calculate the step count because it always returns None. I looked over torch's documentation for step() but couldn't understand exactly why you chose to overide the step function. Kindly review the following PR: #9