Rebuild the structure of openapi

[Freedomfirebody]

重新调整 openapi 相关接口的代码结构，接口现迁移至 openapi 目录下 PR 对应问题单nacos-group/r-nacos#62

[CLAassistant]

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1 out of 2 committers have signed the CLA.

:white_check_mark: Freedomfirebody
:x: Cheng Weiss

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[heqingpan]

需要处理cargo clippy的报警后再合并到master

[Freedomfirebody]

已处理 cargo clippy 的 warning 并 执行了 cargo fmt

[heqingpan]

用项目自带的测试脚本./test_cluster.sh start_debug运行结果还有问题，需要处理下。

[Freedomfirebody]

已调调整代码问题，测试脚本执行通过

[heqingpan]

上面有个nacos社区统一加的license/cla协议，需要签署下才能合并。