* add cpu version, using set: sum, min, max

* add cpu version: mean

* improve cpu code and fix dynamic memory allcation problem

* fix arg error, add index judge, delete fp16

* fix bug in CudaAtomicMax and CudaAtomicMin

* add CUDA version

* fix grad_op bug for index

* add op test, add correct cpu grad op

* Add correct CUDA Mean grad

* [Add] Successful MEAN and SUM

* [Add] Successful MIN and MAX in CPU

* [Add] Successful MIN and MAX in CUDA

* fix windows dtype ci

* fix ROCM ci by adding HIP flag

* rename fused_gather_scatter to send_recv

* unify name as send and recv

* change zero index return time

* add send_recv incubate api

* fix index data type, add unittest case for API

* delete redundant input tensor

* fix en example and docs, add default value in pool_type

* add shape judge and max grid judge

* fix comment

* fix index type bug

* add const &

* fix en docs

* delete numpy in examples

* add unittest for int input

* fix send_recv comment

* change send_recv to graph_send_recv

* softmax mask fuse upper triangle

* cover not implemented cpu code

* update 2.0 public api in all left files

* reverse device.py all list;
fix some flake8 errors

* remove fluid for auto_checkpoint.

* fix bug.

* rm check_import_scipy, rm chunk_eval and mean_iou in paddle.metric.__init__.py

* Revert "rm check_import_scipy, rm chunk_eval and mean_iou in paddle.metric.__init__.py"

This reverts commit 179ba8c2b22bc31fe8d8a126e31820792cbd0f4e.

* delete paddle.metric.chunk_eval and paddle.metric.mean_iou

* delete paddle.nn.clip and paddle.nn.clip_by_norm

* delete paddle.nn.functional.activation.hard_sigmoid and paddle.nn.functional.activation.hard_swish

* delete paddle.nn.Pool2D, paddle.nn.BilinearTensorProduct, paddle.nn.RowConv, paddle.nn.functional.row_conv

* fix extension import error

* fix unittest for row_conv and Pool2D

* 1. remove paddle.unique_with_counts api, which counts as unique api
2. add paddle.math.increment(x, value=1.0, name=None) api
3. replace paddle.sums with paddle.add_n api
4. update paddle.metric.accuracy api (add name parameter)

* fix api alias

* remove cos_sim

* Move paddle/incubate/hapi/metrics to paddle/metric
* Add Precision, Recall and Auc metric

* add base name alias; test=develop

* fix embedding bug; test=develop

* fix io error; test=develop

* add metric; test=develop

* add import palce; test=develop

* add setup; test=develop

* fix incubate reader; test=develop

* fix initializer error; test=develop

* remove unused inference_transpiler unit-tests

test=develop

* remove InferenceTranspiler usage in quantize_transpiler.py

test=develop

* add dist transpiler unit test

* update by comment

* update by comment

* fix ci

* fix ci

* "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