Update mailer previews

Add correct setup data to make mailers work.

Issues
------
- Closes #65

test/mailers/previews/user_mailer_preview.rb

@@ -3,12 +3,15 @@ class UserMailerPreview < ActionMailer::Preview
   # Preview this email at http://localhost:3000/rails/mailers/user_mailer/confirmation
   def confirmation
     @unconfirmed_user = User.find_by(email: "unconfirmed_user@example.com") || User.create!(email: "unconfirmed_user@example.com", password: "password", password_confirmation: "password")
-    UserMailer.confirmation(@unconfirmed_user)
+    @unconfirmed_user.update!(confirmed_at: nil)
+    confirmation_token = @unconfirmed_user.generate_confirmation_token
+    UserMailer.confirmation(@unconfirmed_user, confirmation_token)
   end
 
   # Preview this email at http://localhost:3000/rails/mailers/user_mailer/password_reset
   def password_reset
-    @password_reset_user = User.find_by(email: "password_reset_user@example.com") || User.create!(email: "password_reset_user@example.com", password: "password", password_confirmation: "password")
-    UserMailer.password_reset(@password_reset_user)
+    @password_reset_user = User.find_by(email: "password_reset_user@example.com") || User.create!(email: "password_reset_user@example.com", password: "password", password_confirmation: "password", confirmed_at: Time.current)
+    password_reset_token = @password_reset_user.generate_password_reset_token
+    UserMailer.password_reset(@password_reset_user, password_reset_token)
   end
 end