Aleksei

Unable to specify empty response schema

12

## 🐛 Bug Report [Response schema](https://github.com/grpc-ecosystem/grpc-gateway/blob/master/protoc-gen-openapiv2/options/openapiv2.proto#L224) states that ``` // `Schema` optionally defines the structure of the response. // If `Schema` is not provided, it means there is no content...