* [Refactor] Refactor data_batch type.

* fix sampler

* [Refactor] Remove cur_dataloader in runner.

* fix set_epoch

* [Enhancement] refactor base data elment

* fix comment

* fix comment

* fix pop not existing key without error

* [Refactor] Add batch_idx to hook input.

* update

* [WIP] testvisualizationhook

* add TestNaiveVisualizationHook

* fix comment

* unpad

* batch imdenormalize

* fix comment

* fix comment