* Add XPU plugin to support the customized ops or improve the performance of the fusion ops based on hand-written xpu micro kernels.

* refine README.md

* mv all unittests test

* fix error

* fix error

* fix

* fix

* del unittests

* fix paddle_build.sh

* fix

* fix test

* fix add test

* fix

* fix

* fix

* merge develop

* fix

* fix

* fix

* fix

* fix

* merge develop

* fix test_async_read_write

* fix test_async_read_write

* merge develop

* fix

* fix import legacy_test

* fix

* fix

* fix

* fix

* fix

* fix

* fix

* fix

* fix bug

* fix

* fix coverage test bug

* fix

* fix

* fix

* fix

* fix

* fix code sstyle

* fix code

* fix code

* fix

* fix

* fix

* del test_sequence_enumerate_op.py

* fix

* add simple reformated ci files

* update

* add radme for new unitetsts

* add radme for new unitetsts

* add radme for new unitetsts

* reset mlu

* update for samples

* add base api

* reset some dist unit tests

* add warning in grenerated cmakelists file

* update readme for new dist unit tests

* add all collective tests

* remain base file and launcher file

* Update README.md

* Update README.md

* fix env PYTHONPATH

* Update gen_ut_cmakelists.py

* add all collective tests

* add docs for gen_ut_cmakelists.py

* pretify codes

* commont name == "name"

* update for comments

* update function's help

* update for run type

* update readme

* add all collective tests

* add all collective tests

* mv  collective test files

* update for all collective tests

* update

* update

* update

* update for all tests

* update for checking name

* Update Cmakelists.txt

* update testlist.csv

* remain test_parallel_dygraph_dataparallel in unittests

* set broadcast op all platforms

* update

* remain test_broadcast_tensors_op

* fix

* rm some collective files

* update more colective tests

* update

* update

* update
gen_ut_supports recursion

* update

* update

* update

* update

* fix nccl version

* update

* update

* update

* update

* fix a bug and try to pass

* update

* add csv

* update for timeout

* remove tcp store

* fix

* fix

* update

* update

* update for more dist tests

* move multi node tests

* update

* update

* update

* fix for auto parallele

* update

* update path in python file

* update

* reset some test in unittests

* fix

* update readme

* fix

* update

* fix port

* graph engine demo

* upload unsaved changes

* fix dependency error

* fix shard_num problem

* py client

* remove lock and graph-type

* add load direct graph

* add load direct graph

* add load direct graph

* batch random_sample

* batch_sample_k

* fix num_nodes size

* batch brpc

* batch brpc

* add test

* add test

* add load_nodes; change add_node function

* change sample return type to pair

* resolve conflict

* resolved conflict

* resolved conflict

* separate server and client

* merge pair type

* fix

* resolved conflict

* fixed segment fault; high-level VLOG for load edges and load nodes

* random_sample return 0

* rm useless loop

* test:load edge

* fix ret -1

* test: rm sample

* rm sample

* random_sample return future

* random_sample return int

* test fake node

* fixed here

* memory leak

* remove test code

* fix return problem

* add common_graph_table

* random sample node &test & change data-structure from linkedList to vector

* add common_graph_table

* sample with srand

* add node_types

* optimize nodes sample

* recover test

* random sample

* destruct weighted sampler

* GraphEdgeBlob

* WeightedGraphEdgeBlob to GraphEdgeBlob

* WeightedGraphEdgeBlob to GraphEdgeBlob

* pybind sample nodes api

* pull nodes with step

* fixed pull_graph_list bug; add test for pull_graph_list by step

* add graph table;name

* add graph table;name

* add pybind

* add pybind

* add FeatureNode

* add FeatureNode

* add FeatureNode Serialize

* add FeatureNode Serialize

* get_feat_node

* avoid local rpc

* fix get_node_feat

* fix get_node_feat

* remove log

* get_node_feat return  py:bytes

* merge develop with graph_engine

* fix threadpool.h head

* fix

* fix typo

* resolve conflict

* fix conflict

* recover lost content

* fix pybind of FeatureNode

* recover cmake

* recover tools

* resolve conflict

* resolve linking problem

* code style

* change test_server port

* fix code problems

* remove shard_num config

* remove redundent threads

* optimize start server

* remove logs

* fix code problems by reviewers' suggestions
Co-authored-by: NHuang Zhengjie <270018958@qq.com>
Co-authored-by: NWeiyue Su <weiyue.su@gmail.com>
Co-authored-by: Nsuweiyue <suweiyue@baidu.com>
Co-authored-by: Nluobin06 <luobin06@baidu.com>
Co-authored-by: Nliweibin02 <liweibin02@baidu.com>

* add the support for multi-node training