PyTorch 1.5 comes with stable C frontend API

Following the latest release of the programming language Python, an updated version of the Python package PyTorch is now available. PyTorch is designed to provide Tensor computation and deep neural networks. PyTorch 1.5 features new and updated libraries as well as new API additions and improvements. A highlight of the release is that the C frontend API is now stable and at parity with Python. This includes 100% coverage and docs for C torch::nn module/functional, C__ optimizers that behave the same as the Python equivalent; and the ability to use tensor.index({Slice(),