Pytorch & ONNX Clean up & Improvement
Created by: Duchstf
In this PR:
- Cleaned up and debug ONNX & Pytorch codes.
- Organize ONNX & Pytorch according to Keras scheme.
- Initial support for ONNX & Pytorch from Python API.
The codes were tested and it worked with some of my test models (MLP 2 layers/3layers). Due to problems with CNN backend (no support for channel_first), I didn't test it on any CNN models.
@thesps @vloncar Let me know how I should proceed and if I need to add more tests.
Thanks!