Update README.md

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  - **Dependency**: Microservice dependency management
  - **Separated**: Separated microservice and microservice instance entity management
  - **Domains**: Logical multiple domains management
- - **Security**: White and back list configuration for service discovery
+ - **Security**: White and black list configuration for service discovery
  - **Discovery**: Support query instance by criteria
  - **Subscribe**: Use web socket to notify client about instance change events
  - **[`Portal`](/frontend)**: Awesome web portal