Add questions with mutiple answers to polls public interface

The `reload` method added to max_votes validation is needed because the
author gets here with some changes because of the around_action
`switch_locale`, which adds some changes to the current user record and
therefore, the lock method raises an exception when trying to lock it
requiring us to save or discard those record changes.

app/controllers/polls/questions_controller.rb

@@ -5,9 +5,7 @@ class Polls::QuestionsController < ApplicationController
   has_orders %w[most_voted newest oldest], only: :show
 
   def answer
-    answer = @question.answers.find_or_initialize_by(author: current_user)
-
-    answer.answer = params[:answer]
+    answer = @question.find_or_initialize_user_answer(current_user, params[:answer])
     answer.save_and_record_voter_participation
 
     respond_to do |format|
@@ -15,7 +13,7 @@ class Polls::QuestionsController < ApplicationController
         redirect_to request.referer
       end
       format.js do
-        render :answer
+        render :answers
       end
     end
   end