public async Task<ActionResult> ExternalLoginConfirmation(ExternalLoginConfirmationViewModel model, string returnUrl)
        {
            if (User.Identity.IsAuthenticated)
            {
                return RedirectToAction("Index", "Manage");
            }

            if (ModelState.IsValid)
            {
                // Pegar a informação do login externo.
                var info = await AuthenticationManager.GetExternalLoginInfoAsync();
                if (info == null)
                {
                    return View("ExternalLoginFailure");
                }
                var user = new ApplicationUser { UserName = model.Email, Email = model.Email };
                var result = await _userManager.CreateAsync(user);
                if (result.Succeeded)
                {
                    result = await _userManager.AddLoginAsync(user.Id, info.Login);
                    if (result.Succeeded)
                    {
                        await _signInManager.SignInAsync(user, isPersistent: false, rememberBrowser: false);
                        return RedirectToLocal(returnUrl);
                    }
                }
                AddErrors(result);
            }

            ViewBag.ReturnUrl = returnUrl;
            return View(model);
        }
        public async Task<ActionResult> Register(RegisterViewModel model)
        {
            if (ModelState.IsValid)
            {
                var user = new ApplicationUser { UserName = model.Email, Email = model.Email };
                var result = await _userManager.CreateAsync(user, model.Password);
                if (result.Succeeded)
                {
                    await _signInManager.SignInAsync(user, isPersistent:false, rememberBrowser:false);

                    var code = await _userManager.GenerateEmailConfirmationTokenAsync(user.Id);
                    var callbackUrl = Url.Action("ConfirmEmail", "Account", new { userId = user.Id, code = code }, protocol: Request.Url.Scheme);
                    await _userManager.SendEmailAsync(user.Id, "Confirme sua Conta", "Por favor confirme sua conta clicando neste link: <a href='" + callbackUrl + "'></a>");
                    ViewBag.Link = callbackUrl;
                    return View("DisplayEmail");
                }
                AddErrors(result);
            }

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