* Add API inference in the docs and fix readthedocs config.
* Replace some relative link in docs.
* Format docstring for reStructuredText syntax.
* Fix vit paper link
* Fix docstring of `show_results` function in `BaseClassifier`.
* Refector label smooth loss, now support mode `original`, `classy_vision`
and `multi_label`.
* Add unittests for label smooth loss.
* Improve docstring of LSR
* add convert_to_one_hot
* add test_label_smooth_loss
* add my label_smooth_loss
* fix CELoss bug
* test new label smooth loss
* LabelSmoothLoss downward compatibility
* add some comments
* remove the old version of LabelSmoothLoss
* add some comments
* add some comments
* add some comments
* add label smooth to config