* move operators/math/math_function_* to pten/kernels/func
* namespace from `paddle::operators::math` to `pten::funcs`

* Merged LoDTensor with Tensor,test=allcases

* Patched python level LoDTensor

* Patched python level LoDTensor

* Merge Tensor into DenseTensor

* Fixed namespace issues,test=allcases

* Fixed merge issues

* Fixed inference issues

* Fixed NPU test issues

* Fixed merge issues

* Merged LoDTensor with Tensor,test=allcases

* Patched python level LoDTensor

* Fixed example code failure

* Polished function names, removed duplicated forward declarations

* add PullSparseValue for pull sparse

* fix bug for PullSparseValue

* add test mode in lookuptable

* revert API change

* add comment for is_training

* fix entry

* fix distributed lookup table fuse case

* fix entry bug at first time

* move entry from paddle.fluid -> paddle.distributed

* fix ut with paddle.enable_static()
Co-authored-by: Nmalin10 <malin10@baidu.com>

* use iwyu clean include second time, test=develop

* rename sendrecv.proto to namespace paddle.distributed

* split ps with distributed

* add tensor table

* add service, remove ut on mac

* fix heter_profiler & add heter stop method

* fix code style