* batch_norm momentum support variable. test=develop

* fix format. test=develop

* add batch_norm momentum variable example. test=develop

* move MomentumTensor to training branch. test=develop

* split example. test=develop

* fix doc. test=develop

* fix PADDLE_ENFORCE ci. test=develop

* fix format. test=develop

* support data_norm_op run in CUDA
* add two parameters sync_stats & summary_decay_rate
* add UT

* add the framework support for distfc and ut, test=develop
* fix the implementation of shard_index_op, test=develop

pass the argument `allow_out_of_range` of one_hot op to c++ back end.

* fix auc drop first commit test=develop

* update datanorm op

* update datanorm with enforce test=develop

* update test=develop

* update format test=develop

* update format

* update format test=develop

* add unit test test=develop

* update unit test test=develop

* update format test=develop

* update format test=develop

* update API description test=develop

* update API description test=develop

* update format test=develop

* fix codes as comments test=develop

* fix description as comments test=develop

* fix description as comments test=develop

* update codes.. test=develop

* modified error message for conv and conv_transpose, test=develop

* modified doc of conv and conv_transpose op, test=develop

* modified the expression for error message, test=develop

* modified error message for group_norm op, test=develop

* modified detail of Attr(data_format) or Attr(data_layout)

* add ValueError in API doc for maxout op, test=develop

* add input type and dtype check template, and update some APIs check

* refine check template, and update some APIs check in nn.py

* update some APIs check in loss.py

test=develop

* Split some APIs from nn.py to loss.py

test=develop

* fix test_detection unit-test

test=develop

* set the default value of alpha for prelu to 0.25, test=develop

* add the call to __syncthreads(), test=develop

* fix the implementation of cpu prelu, test=develop

* repair the implementation of element mode prelu, test=develop

* modify test_prelu_op.py, test=develop

* split some APIs from nn.py to rnn.py

* split some APIs from nn.py to sequence_lod.py

test=develop

* fix unit-test bug

test=develop

* fix test_layers unit-test bug

test=develop

* fix uniform random; test=develop

* add uniform random test; test=develop

test=develop

* maxout support channel_last input, test=develop

* modified details of Input(X) and Attr(groups, axis) in doc, test=develop

support Tensor for split and concat, support -1 in num_or_sections, add check num_or_sections (#20780)

* improve split and concat op:
1. support Tensor for argument 'dim' in split op.
2. support Tensor for argument 'axis' in concat op.
test=develop

* redefine function GetDataFromTensor and set unknown output shape to - 1.
test=develop

* add check: Attr(sections) match Input(X). test=develop

* support Tensor for attr(sections) and attr(sections) can contain -1.
add check for attr(sections).
test=develop

* modify error message for concat and call Resize only when necessary. test=develop

* improve unsqueeze op to support int, Tensor and Tensor list for argument axes.
test=develop

* call Resize only when necessary. test=develop

*  Make shape tensor support int32

* All elements in attr(shape) of crop_tensor can be -1, test=develop, test=document_preview

* fix the bug that attr(offsets) should be initialized, test=develop

* update the infer shape of matmul,  test=release/1.6

* add unittests of matmul, test=release/1.6

* change func names, test=develop

* fix elementwise_floordiv_op and elementwise_mod_op, test=develop

* fix API.spec, test=develop

* fix API.spec, test=develop

* fix error message for elementwise_add/mul;test=develop

* fix type error message;test=develop

* add data type check, test=develop

* polish error messages, test=develop

* polish error messages, test=develop

* Remove support for the CPU architecture matmul, test=develop

* fix syntax bug, test=develop

* add expand_as op, test=develop

* add expand_as op,test=develop

* add expand_as op,test=develop

* add nn.py, test=develop

* delele paddle_enforce, test=develop

* Fix docs of gru_unit and dynamic_gru.

Fix basic_gru in rnn_impl.py.

Add error messages for param_attr setting in layer_norm api.

Add int64 dtype for expand.

test=develop

* Reopen unit-tests of basic_gru/basic_lstm in rnn_impl.py.
test=develop

* Add unit test for layer_norm api.
test=develop

* Remove the deprecated gru doc fix. test=develop

* Fix basic_gru test coverage. test=develop

* Update API.spec. test=develop

* Update API.spec. test=develop

* Fix test_basic_gru coverage test. test=develop

* Update test_basic_gru in test_layers to use fluid.data
test=develop

* Update test_basic_gru for coverage. test=develop

* Refine error message of transpose.
* Fix transpose, multiplex, unsqueeze, unstack. test=develop, test=document_preview, test=document_fix

* disable nccl test

* Update version.

* fix term core only

* fix transpiler error

* fix protobuf memory leak (#11177)

fix protobuf memory leak

* "change eigen mirror"

* refine en doc sequence enum pad expand mask d2s

* refine seq enum expand mask pad test=develop, test=document_fix

* remove cn char test=document_fix

* spec test=document_fix

* code style test=document_fix

* test=document_fix

* test=document_fix

* test=document_fix

* test=document_fix

* test=document_fix

* test=document_fix

refine the en api doc of ones, zeros, reverse, assign, increment, hsigmoid and create_py_reader_by_data ops (#20343)

* refine the en api doc of ones, zeros, reverse, increment, hsigmoid and create_py_reader_by_data ops
test=develop, test=document_preview, test=document_fix

* refine eng doc for hsigmoid and create_py_reader_by_data ops
test=develop, test=document_preview, test=document_fix

* update API.spec
test=document_fix

* Fix the parameter name axis of reverse op in eng doc
test=develop, test=document_fix

* Update API.spec
test=develop, test=document_fix

* Refine eng doc of zeros, ones, reverse and assign op
test=develop, test=document_fix

* Update API.spec for assign, ones, zeros and reverse
test=develop, test=document_fix

* Fix data type of reverse op in eng doc
test=develop, test=document_fix

* Update API.spec for reverse op
test=develop, test=document_fix

* fix_norm_model_average_bug

* test=develop

* refine comment test=develop

* refine comment test=develop