Update README.md

Author: sksq96

README.md

@@ -198,3 +198,8 @@ Estimated Total Size (MB): 0.78
 - The idea for this package sparked from [this PyTorch issue](https://github.com/pytorch/pytorch/issues/2001).
 - Thanks to @ncullen93 and @HTLife. 
 - For Model Size Estimation @jacobkimmel ([details here](https://github.com/sksq96/pytorch-summary/pull/21))
+
+### License
+
+`pytorch-summary` is MIT-licensed.
+