* add dist erfinv gumbel softmax

* fix test gumbel softmax op bug

* try to fix gumbel softmax error

* add label smooth backlist

* add bn cpu version; test=develop

* move batch norm to pten

* move batch norm to pten; test=develop

* fix bug; test=develop

* fix func::tranpose depend bug; test=develop

* fix compile bugs; test=develop

* fix use_op batch_norm bug; test=develop

* fix cudnn bn add relu test; test=develop

* fix pten context build and double grad bug; test= develop

* remve useless code; test=develop

* add batch norm gpu fp16 support; test=develop

* fix test bn op bug; test=develop

* remove output dtype set; test=develop

* fix bug; test=develop

* fix bug; test=develop

* fix applay pass to program bug; test=develop

* revert to develop; test=develop

* fix rocm bug; test=develop

* revert operator to develop; test=develop

* fix pre_commit; test=develop

* fix statci check error; test=develop

* resolve conflict; test=develop

* ana batch norm bug;

* revert batch norm op

* resolve conlict

* fix nan inf and speed bug; test=develop

* fix bug; test=develop

* fix error; test=develop

* test expand op; test=develop

* fix bug; test=develop

* resolve confilct

* resolve confilct; test=develop

* polish code; test=develop

* polish code; test=develop

* change mutable data to ctx alloc; test=develop

* make format same with ci; test=develop

* fix format error with ci; test=develop

align expand_as op to expand.

* adaptive expand op to 2.0 (align to torch.expand) , test=develop

affine_channel, affine_grid, bilinear_interp, bilinear_tensor_product,
clip, crop, crop_tensor, cumsum, data_norm, expand, expand_as

sequence_unpad, expand, pad, pad_constant_like,
norm, bilinear_tensor_product, flatten2, im2sequence,
unpool, cos_sim, strided_slice, flatten, elementwise_min,
abs, acos

test=develop

* fix PythonAPI test in Op unittest, test=develop
* fix unit tests that do not need to inherit OpTest, test=develop

2. fix bug in backward.py: using fill_constant instead of fill_constant_batch_size_like
3. fix bug in ExpandGradOp.

test=develop

* fix expand bug test=develop

* fix style test=develop

* fix style test=develop

* fix style test=develop

* fix style test=develop

1. add tensor support for argument expand_times in expand op;
2. add support parameter inference when argument expand_times is a list containing integer and tensor variable;

improve expand op according to reviews:
1. add doc of ExpandTimes in expand_op.cc;
2. improve the test of test_api.

add stop_gradient=True when attr(expand_times) is tensor Variable, change code examples.
test=develop,test=document_preview

* expand support tensor attribute; test=develop

* fix bug ; test=develop

* fix uni test bug; test=develop

* fix copy bug; test=develop

* refine expand_times default value; test=develop

Currently, our tests run with 2 GPUs, the init time is absurdly long:
about 4s for each process.  Currently, we run each OP test on
different processes. This PR:

1. create cmake function py_test_modules which will generate the
Makefile that runs a list of Python unittest module in a single Python
process.

2. move all "python unittest compatible" (e.g., used the unittest
package, not just a regular python file). from fluid/tests to
fluid/tests/unittests.

3. cmake now will run all OP tests in fluid/tests/unittests in a
single process, except the time-consuming tests, they are separated
into different processes to utilize parallelism. Please make sure to
use the unittest package if you put the python test file in
fluid/tests/unittests

4. remove all exit(0) from fluid/tests/unittests/*.py, exit(0) is used
to disable unittest, we can not do it when running all tests in a
single process since it will terminate the process without running the
other tests. Instead, the test is disabled in
fluid/tests/unittests/CMakeLists.txt. FIXME is added for each disabled
item. Please disable the unittest from
fluid/tests/unittests/CMakeLists.txt, instead of adding exit(0) to the
Python file, for all Python file in fluid/tests/unittests/.

5. add an option WITH_FAST_BUNDLE_TEST. When OFF, will run the unit
tests in separate process so that they can be tested individually.

* "fix decode bug"

* "follow commnet"

* "fix error"

* "fix hook bug"

* fix based comment

* fix copyright

* fix based on comment

* add copyright hook

* add copyright hook

* refine copyright hook

* "test copyright hook"

* fix check style

* fix ci

* init commit

* change some dir name