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

            app.Use(typeof(GithubAuthenticationMiddleware), app, options);
            return app;
        }
        public static IAppBuilder UseGithubAuthentication(this IAppBuilder app, GithubAuthenticationOptions options)
        {
            if (app == null)
            {
                throw new ArgumentNullException("app");
            }
            if (options == null)
            {
                throw new ArgumentNullException("options");
            }

            app.Use(typeof(GithubAuthenticationMiddleware), app, options);
            return(app);
        }