* [Auto Parallel] Suppport different dataloaders

* [Auto Parallel] Add num_shards config for dataset

* [Auto Parallel] Unify the logger and outputs of Engine API

* [Auto Parallel] Fix the bugs of to_static

* [Auto Parallel] Adjust the test_to_static.py

* [Auto Parallel] Add the prepare API and replace __call__ with run

* [Auto Parallel] Improve the private implementations of Engine

* [Auto Parallel] Set capacity of dataloader for opt tuning

* [Auto Parallel] [WIP] Change the fine-grained API

* [Auto Parallel] Improve APIs to support different user cases

* [Auto Parallel] Add removed config

* [Auto Parallel] Add imports

* [Auto Parallel] Fix bugs for to_static

* [Auto Parallel] Remove unnecessary imports