public async Task<JsonResult> JsonLogin(LoginViewModel model, string returnUrl)
        {
            if (this.ModelState.IsValid)
            {
                var user = await this.UserManager.FindAsync(model.Email, model.Password);
                if (user != null)
                {
                    await this.SignInAsync(user, model.RememberMe);
                    return this.Json(new { success = true, redirect = returnUrl });
                }
                else
                {
                    this.ModelState.AddModelError("", "The user name or password provided is incorrect.");
                }
            }

            // If we got this far, something failed
            return this.Json(new { errors = this.GetErrorsFromModelState() });
        }
        public async Task<ActionResult> Login(LoginViewModel model, string returnUrl)
        {
            if (this.ModelState.IsValid)
            {
                var user = await this.UserManager.FindAsync(model.Email, model.Password);
                if (user != null)
                {
                    await this.SignInAsync(user, model.RememberMe);
                    return this.RedirectToLocal(returnUrl);
                }
                else
                {
                    this.ModelState.AddModelError("", "Invalid username or password.");
                }
            }

            // If we got this far, something failed, redisplay form
            return this.View(model);
        }