Doesn't handle multiple inputs correctly

[amaurylancelin]

Hi,
if we want to use torchsummary with multiple inputs, with let's say an input like that [(1, 16, 16), (1, 28, 28)], it would not work properly (for the printed input size) and could lead to errors if len(input_1.shape) != len(input_2.shape) for instance. We would want to sum the product of shapes of each input.
Then, is just a simple fix you have to make.