public static IAppBuilder UseApiKeysAuthentication(this IAppBuilder app, ApiKeysAuthenticationOptions options)
        {
            if (app == null)
            {
                throw new ArgumentNullException("app");
            }

            app.Use <ApiKeysAuthenticationMiddleware>(options);
            app.UseStageMarker(PipelineStage.Authenticate);
            return(app);
        }
        public static IAppBuilder UseApiKeysAuthentication(this IAppBuilder app, ApiKeysAuthenticationOptions options)
        {
            if (app == null)
            {
                throw new ArgumentNullException("app");
            }

            app.Use<ApiKeysAuthenticationMiddleware>(options);
            app.UseStageMarker(PipelineStage.Authenticate);
            return app;
        }