* enable build milvus on centos7

* Update build enviroment Centos7 dockerfile

* Update Dockerfile

* Update Dockerfile

* Update Dockerfile

* Update Dockerfile

* Update Dockerfile

* Update Dockerfile

* Update Dockerfile

* add centos7_build_deps.sh

* add centos7 build cpu version enviroment

* add centos7 on github actions

* fix bug

* fix bug

* fix bug

* update ci/docker/centos-7-core.dockerfile

* fix github actions bug

* update centos7 case on github actions

* update docker-compose.yml

* debug centos case on github actions

* debug centos case on github actions

* add centos7 deploy dockerfile

* #665 support get/set config via CLI

* #665 support get/set config via CLI

* #665 add unittest for config CLI

* #665 remove config_node_map_

* #665 remove config_node_map_

* #665 fix clang-format

* #665 fix clang-format

* #665 update changelog

* #665 code clean

* #665 update API interface

* #665 update API interface

* #665 handle server status

* #665 handle unknown command

* #665 update debug log

* #665 support get/set config via CLI

* #665 support get/set config via CLI

* #665 add unittest for config CLI

* #665 remove config_node_map_

* #665 remove config_node_map_

* #665 fix clang-format

* #665 fix clang-format

* #665 update changelog

* #665 code clean

* #665 update API interface

* #665 update API interface

* #665 handle server status

* #665 handle unknown command

* #665 update debug log

* #665 support get/set config via CLI

* #665 support get/set config via CLI

* #665 add unittest for config CLI

* #665 remove config_node_map_

* #665 remove config_node_map_

* #665 fix clang-format

* #665 fix clang-format

* #665 update changelog

* #665 code clean

* #665 update API interface

* #665 update API interface

* #665 handle server status

* #665 handle unknown command

* #665 update debug log

* #665 rollback CmdRequest.cpp

update github actions core.yml

* add github actions

* add amd64-ubuntu-18.04-cache volumes

* update core.yml in github actions

* update ci/docker/ubuntu-18.04-core.dockerfile

* update CI scripts file

* update github actions

* update github actions

* update github actions

* remove Travis CI

* update docker-compose.yml

* update ci scripts files

* update docker-compose.yml

* refactoring(create_table done)

* refactoring

* refactor server delivery (insert done)

* refactoring server module (count_table done)

* server refactor done

* cmake pass

* refactor server module done.

* set grpc response status correctly

* format done.

* fix redefine ErrorMap()

* optimize insert reducing ids data copy

* optimize grpc request with reducing data copy

* clang format

* [skip ci] Refactor server module done. update changlog. prepare for PR

* remove explicit and change int32_t to int64_t

* Add log to debug #678

* Rename nsg_mix to RNSG in C++ sdk #735

* [skip ci] change __function__

* clang-format

* Add log to debug #678

* Rename nsg_mix to RNSG in C++ sdk #735

* [skip ci] change __function__

* add TracerUtil

* Interceptor ok

* add handler

* add context

* minor update

* keep span in trace context

* add span in search okay

* Update Context.cpp

* refactor

* refactor

* refactor

* format

* add context in SearchJob

* trace search okay

* add back finish span in interceptor

* add namespace

* add tracing config in server config

* add random id

* debug mode okay

* update CMakeLists

* add opentracing to cmake

* update unittest

* add tracing namespace

* remove std::run_time error

* add lock when erasing context_map

* update tracing config

* lint

* update CHANGELOG

* small fix

* fix server unit test

* fix scheduler unit test

* fix db unit test

* lint

* fix db unit test gpu version

* rename to tracing_config

* fix

* update

* trigger ci

* docs: update README.md [skip ci]

* docs: update .all-contributorsrc [skip ci]