Support cmake and update some submodule

[vermorth]

changes:

• remove submodule gmock
• remove submodule protobuf
• add submodule googletest v1.10.0 to third_party/googletest
• add submodule grpc v1.37.0 to third_party/grpc
• update submodule leveldb to v1.23
• support cmake

Maybe more tests are needed to confirm correctness and stability.

[tencent-adm]

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[vermorth]

You can compile with the following command:

git clone --recurse-submodules https://github.com/vermorth/phxpaxos.git
cd phxpaxos

pushd third_party
./autoinstall.sh
popd

mkdir -p build
cd build

cmake \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX=/usr/local/phxpaxos \
    -DPHXPAXOS_BUILD_TOOLS=ON \
    -DPHXPAXOS_BUILD_UT=ON \
    -DPHXPAXOS_BUILD_TEST=ON \
    -DPHXPAXOS_BUILD_BENCHMARK=ON \
    -DPHXPAXOS_BUILD_PLUGIN=ON \
    -DPHXPAXOS_BUILD_SAMPLE_ECHO=ON \
    -DPHXPAXOS_BUILD_SAMPLE_ELECTION=ON \
    -DPHXPAXOS_BUILD_SAMPLE_KV=ON \
    ..

make
make install

[USTB-JXY]

如遇见

可以将 phxpaxos/CMakeLists.txt 里的
"${PROJECT_SOURCE_DIR}/third_party/local_install/abseil/lib64/cmake/absl" 改为
"${PROJECT_SOURCE_DIR}/third_party/local_install/abseil/lib/cmake/absl"