Support rest

### Is your feature request related to a problem?

Rest is still play an import part in real projects. If the grpc framework could support it, it will be great. It seems that grpc donet still have some experimental project for it : https://github.com/grpc/grpc-dotnet/issues/167
### Describe the solution you'd like

### Describe alternatives you've considered

### Additional context

Start by reviewing the linked grpc-dotnet issue 167 and the grpc-java project context to determine the intended scope of REST support. The issue does not name Java files, tests, an entry point, or a precise solution; done would require an agreed REST integration design and corresponding implementation and validation.

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