This reverts commit 35fc732dadac4761852b18512b5c5df8785e36df.

This reverts commit 376d83d4.

This reverts commit fad5c8e3.

This reverts commit 0e28a39d.

This reverts commit 0d7e595f.

This reverts commit 187f38eb.

This reverts commit 5a6fe171.

This reverts commit 32593b63.

This reverts commit d3b7690f.

1. rm Global.eval_mode
2. add Global.task
3. mv type_name to ppcls.utils
4. build dataloader, loss, metric by mode

1. ModelSaver();
2. _build_ema_model();
3. _init_checkpoints();
4. others.

* add mgd loss

* add init

* fix doc