Update joinus.png

* add new load dygraph func

* update load_pretrain_params

* update load_dygrah_params

* Update save_load.py

* Update train.py

* Update save_load.py

* return {} when path is None

* return {} when path is None

fix save_log_path as null

save visualized image

rename structure 2 table

add train code for table

Update joinus.png

add warmup

add layout doc

Update joinus.png

delete benchmark utils