* refine format

* update doc

* handle uninitialized tensor

* add ut

* Fix xpu notest;test=kunlun

* fix

* test=kunlun

* test=kunlun

* add sharding

* add compile limit for paddle enforce

* polish elementwise_op_function.cu.h

* fix failed unittest

* fix windows compile failed

* detail polish

* revert no type constructor

Recently, test_parallel_executor_test_while_train randomly failed on CI. On all CI logs, it showed NCCL initialization failed or cusolver initialization failed. I found online that those failure is usually caused by GPU shortage. Those API calls CUDA APIs directly so it shouldn't be the problem of allocator. It may be somewhere in PaddlePaddle increases GPU usage.

However, I run this test for 1000 times on my machine and the CI machine, either of them can reproduce the random failure. Maybe there is something related to the environment only happened in test env.

To verify my assumption that somewhere in PaddlePaddle increases GPU usage and also fix this CI, I decreased the batch_size to see whether the random failure disappears in test env.

* fix strided_slice_op's GetExpectedKernelType when input tensor is at CUDAPinnedPlace

* add unittest for tensors in cuda pinned place

* skip test for cuda pinned place on cpu machines

* fix optimizer init

* Enhance the detection of whether to keep the build directory

* Enhance the detection of whether to keep the build directory

* fix bug of fetch_async_op_handle

* revert some changes of test_buffer_shared_memory_reuse_pass

* revert some changes of test_buffer_shared_memory_reuse_pass

* remove some judgement

* fix len(outputs) == 1

* update hapi predict interface

* fix code style

* fix docs

* fix docs

* fix docs

* update docs

* fix codes style

* fix unittest

* fix unittest

* fix coverage

test=develop

* update dockerfile

* update dockerfile

* update dockerfile

* update dockerfile

* add opencv in ci

* update cidockerfile

* test nccl

* fix diff

* fix dockerfile

* update ubuntu nccl2.7.8

* update ubuntu nccl2.7.8

* modify ut cmakefile, test=develop

* rename manual_seed to seed

* rename xxx1d-->xxx1D, xxx2d-->xxx2D, xxx3d-->xxx3D

* rename manual_seed --> seed

* do not rename .cc, .cu and .h file

* rename manual_seed --> seed

* rename manual_seed --> seed

* rename manual_seed --> seed

* rename manual_seed --> seed

* disable_static on doc example code

* donot change manual_seed on generator

* add enable_static on sample code

* convert python/paddle/fluid/layers/nn.py to bak

* fix typo

* fix code style

* fix seed to manual_seed when call functions of Generator()

* fix bug

* add static_mode_white_list

* add Mac CI static list

* add Win CI white_list

* add Coverage and Py3 CI white_list, add test_unittest

* nccl init support hostname and ip; test=develop

* Add new api: is_tensor

* Add new api: is_tensor

* Add new api: is_tensor

* Add new api: is_tensor

* Add build paddle inference;test=document_fix

* Add build paddle inference;test=document_fix

* fix generate_proposal_labels in cascade-rcnn series model, test=develop

* fix example code & unittest, test=develop

* update code from review comments, test=develop