Support for Sign and LogSoftmax

[teobaluta]

Hi there,

I would like to add support for Sign and LogSoftmax -- I think I managed to write them up. @nerox8664 how can I test my code so I can submit a PR?

Thanks!

[gmalivenko]

Hello, @teobaluta . You can see how the code is being tested at test/ . If it's impossible to test your code with PyTorch to ONNX conversion, you can use any other framework to get the ONNX model first (and to use its prediction as a real value). If you don't want / don't know how to implement this kind of tests, you can leave code untested, but add warnings about that. Thank you for you interest in the project.