* remove function sequence_conv_pool

* fix test_glu.py

* remove function scaled_dot_product_attention

* remove function img_conv_group

* remove function simple_img_conv_pool

* delete the nets.py

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* Update test_image_classification.py

* Update test_recognize_digits.py

* Update test_recommender_system.py

* Update test_image_classification_fp16.py

* fix bug

* fix bug

* fix bug

* remove the nets.py in fluid

* fix bug

* fix the codestyle

* fix conflict

* fix bug

* Fix TODO