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

            if (options == null)
            {
                throw new ArgumentNullException("options");
            }

            return(app.Use(typeof(FoursquareAuthenticationMiddleware), app, options));
        }
        public static IAppBuilder UseFoursquareAuthentication(this IAppBuilder app, FoursquareAuthenticationOptions options)
        {
            if (app == null)
            {
                throw new ArgumentNullException("app");
            }

            if (options == null)
            {
                throw new ArgumentNullException("options");
            }

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