[Java] Retrofit2-rx settings

Description

I'm not able to figure out how to set settings like endpoint url into generated ApiClient.

Up to now, I've used this code:

    ApiClient apiClient = new ApiClient(); <<<<<<<???????????
    apiClient.addAuthorization("", new LivingOAuthInterceptor());
    ClientApi clientAPI = apiClient.createService(ClientApi.class);
		
    Observable<Void> s = clientAPI.deleteReferenceToken("refToken");
    s.subscribe();

Swagger-codegen version

2.3.0 (built from last 2.3.0 branch commit)

Command line used for generation

PS D:\projects\living\references\swagger_codegen\bin\windows> java -jar D:\projects\living\references\swagger_codegen\mo
dules\swagger-codegen-cli\target\swagger-codegen-cli.jar generate -i http://guest1:8080/authz/cmng/swagger.json -l java
-o authz\java -c config.json

where config.json is:

{
  "library": "retrofit2",
  "artifactId": "swagger-authz-retrofit2-rx",
  "modelPackage": "com.living.authz.client.model",
  "apiPackage": "com.living.authz.client.api",
  "useRxJava2": true,
  "hideGenerationTimestamp": true
}

Start by inspecting the generated ApiClient and the retrofit2 configuration in config.json, using the shown generation command as the entry point. Determine how the endpoint URL is expected to be configured and whether the generated client supports it; done means the configuration path is established or the missing behavior is clearly reproduced.