1. Support csanmt exporting to savedmodel format
2. Create a new base class for text-ranking preprocessors, and move some parameters of mgeo_ranking_preprocessor to init method
3. Avoid Model & Preprocessor classes coupled with pytorch
4. Regression test supports comparing only model output
5. Support zero-shot exporting to onnx and torchscript
Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/11522461
1. Exporting: Support text-classification of bert and tensorflow2.0 models, test cases have been added.
2. Downloading of preprocessor.from_pretrained will ignores some large files which not needed by extension file name.
3. Move sentence-piece-preprocessor to the subclass of text-generation-preprocessor and keep the original name for compatibility.
4. Remove some useless codes in nlp-trainer and trainer.
Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/11206922
