Ensemble BiRefNet codes to HF to load model with weights in one line.

Add guideline to use BiRefNet. Remove codes of model.

Move all BiRefNet github codes to the first level directory.

Move all BiRefNet github codes to the first level directory.

Move all BiRefNet github codes to the first level directory.

Move all BiRefNet github codes to the first level directory.

Move all BiRefNet github codes to the first level directory.

Move all BiRefNet github codes to the first level directory.

For users to load in one key.

For users to load in one key.