public Task<IdentityResult> CreateAsyncUser(ApplicationUser username, string paswoord)
 {
     return Manager.CreateAsync(username, paswoord);
 }
 private async Task SignInAsync(ApplicationUser user, bool isPersistent)
 {
     AuthenticationManager.SignOut(DefaultAuthenticationTypes.ExternalCookie);
     var identity = await UserRepository.Manager.CreateIdentityAsync(user, DefaultAuthenticationTypes.ApplicationCookie);
     AuthenticationManager.SignIn(new AuthenticationProperties() { IsPersistent = isPersistent }, identity);
 }