* make audio requirements optional
 * add changelog for version v0.2
 * add numpy constraint for compatibility with tensorflow1.15
 * update faq
 * fix nlp requiring tensorflow
 * add torchvision to multimodal dependency
 * bump version from 0.2.1 to 0.2.2
 * add warning msg when tensorflow is not installed
 
Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/9268278

* add self-hosted repo:
* add extra requirements for different field and reduce necessary requirements
* update docker file with so required by audio
* add requirements checker which will be used later when implement lazy import
* remove repeated requirements and replace opencv-python-headless with opencv-python

example usage:
```shell
pip install model_scope[all] -f https://pai-vision-data-hz.oss-cn-zhangjiakou.aliyuncs.com/release/maas/repo.html
pip install model_scope[cv] -f https://pai-vision-data-hz.oss-cn-zhangjiakou.aliyuncs.com/release/maas/repo.html
pip install model_scope[nlp] -f https://pai-vision-data-hz.oss-cn-zhangjiakou.aliyuncs.com/release/maas/repo.html
pip install model_scope[audio] -f https://pai-vision-data-hz.oss-cn-zhangjiakou.aliyuncs.com/release/maas/repo.html
pip install model_scope[multi-modal] -f https://pai-vision-data-hz.oss-cn-zhangjiakou.aliyuncs.com/release/maas/repo.html

```
Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/9211383

1.  refactor maaslib to modelscope
2.  fix UT error
3.  support pipeline which does not register default model

Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/8988388

* add trainer interface
 * add trainer script
 * add model init support for pipelineadd pipeline tutorial and fix bugs 
 * add text classification evaluation to maas lib 
 * add quickstart and prepare env doc
 * relax requirements for torch and sentencepiece
 * merge release/0.1 and fix conflict
 * modelhub support for model and pipeline

 Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/8868339

1. add build_doc linter script
2. add sphinx-docs support
3. add development doc and api doc
4. change version to 0.1.0 for the first internal release version

Link: https://code.aone.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/8775307