* support reset param with None value

* add unittest
test=develop

* update unittest
test=develop

* add get delay for multiprocess data loader, test=develop

* add unittest for coverage ci, test=develop

* add timeout unittest, test=develop

* increase the delay time, test=develop

* Add TopK Op Grad CPU&GPU Kernel test=develop

* Add TopK Op Grad, modify grad op maker test=develop

* Add TopK Op Grad, modify grad op maker test=develop

* Add TopK Op Grad, modify PADDLE_ENFORCE test=develop

* Add TopK Op Grad, modify PADDLE_THROW test=develop

* Add TopK Op Grad, modify unittest test=develop

* fix ngraph top k op unittest test=develop

Modify english document and unittest of while_loop

* split unittests in data loader test, test=release/1.7

* split unittests to different files, test=develop

* remove repeat unittest, test=develop

pretty print for communicator flag

test=develop

test=develop

* update ops's unittest of elementwise_pow, elementwise_max, elementwise_min, scale and sqrt
1. update elementwise_pow, elementwise_max and scale's unitests with input data type (float32 -> float64)
2. fix bug that the elementwise_pow doesn't meet threshold requirements with tackling float64 data
3. remove sqrt from op_accuracy_white_list.py
4. update the unittests of elementwise_pow, elementwise_max and elementwise_min ops that their input data shape over 100
5. test=develop

* modify the writing style according suggestions
test=develop

* add deprecated for distribute transpiler, will delete it after 2.0.0, test=develop

当一个模型中有多个fc_lstm子图的时候，且其中fc共用了同一个persistable的bias，此时不应该将bias节点删除，只将非persistable的节点去除即可。

* reproduce match error, test=develop, test=document_fix

* fix mismatch error, test=develop, test=document_fix

* support  golang inference

As the title.

* test=develop fix doc of detection's img_info param

* enhance load program state; test=develop

* optimize commet; test=develop

* 1. optim multihead matmul: fuse three fc to multihtead matmul

test=develop

* fix conflict
test=develop

* fix comments
test=develop

As the title

test=develop

test=develop

* Add support for dynamic_decode(while) training. test=develop

* Fix assign_op and tensor_array_read_write_op after solving conflict. test=develop

* Fix test_rnn_decode_api.py. test=develop

* Refine docs for apis in rnn.py. test=develop

* Adjust outputs of dynamic_decode. test=develop

* Remove the force_cpu update in assign_op. test=develop

* Remove the force_cpu update in assign_op. test=develop

* Make RNNCell.get_initial_states support batch_dim_idx argument. test=develop

* Rename _create_array_outof_while as _create_array_out_of_while in rnn.py.
test=develop

* add thread barrier for the compiled program

* a test for Ernie QAT INT8 accuracy check

test=develop

* Remove NLP comparison test to split PRs

test=develop

* Fix typo and tabs, delete commented lines

test=develop

* re-combine the 2 PRs, test=develop
Co-authored-by: NMichał Gallus <sand3r@interia.eu>
Co-authored-by: Nbingyanghuang <33643817+bingyanghuang@users.noreply.github.com>

* support slice double grad, test=develop
* merge two doublegradopmaker to one doublegradopmaker,test=develop
* change the shape of slice_OP's unittest, test=develop

Refine PaddleBox Framework, Main functions: 
* Add MetricMsg util class, which can calculate metrics like AUC, bucket_error, COPC.
* Replace FeedPass with new interface: BeginFeedPass & EndFeedPass
* Refactor Pull/Push Sparse Function in box_wrapper.
* Use CUDA Kernel to copy keys and copy feasign between tensor and boxps struct.
* Cache copied keys in pull sparse in order to reuse it in push period.