Remove poll votation types

Unfortunately this feature wasn't properly reviewed and tested, and it
had many bugs, some of them critical and hard to fix, like validations
being skipped in concurrent requests.

So we're removing it before releasing version 1.1. We might add it back
in the future if we manage to solve the critical issues.

This commit reverts commit 836f9ba7.

app/controllers/polls_controller.rb

@@ -20,26 +20,13 @@ class PollsController < ApplicationController
   def show
     @questions = @poll.questions.for_render.sort_for_list
     @token = poll_voter_token(@poll, current_user)
-    @poll_questions_answers = Poll::Question::Answer.visibles
-                                                    .where(question: @poll.questions)
+    @poll_questions_answers = Poll::Question::Answer.where(question: @poll.questions)
                                                     .where.not(description: "").order(:given_order)
 
     @answers_by_question_id = {}
-
-    @last_pair_question_answers = {}
-    @questions.each do |question|
-      @answers_by_question_id[question.id] = question.answers.by_author(current_user).pluck(:answer)
-
-      if question.enum_type&.include?("answer_couples")
-        last_pair = question.pair_answers.by_author(current_user).first
-        last_pair ||= generate_and_store_new_pair(question)
-        @last_pair_question_answers[question.id] = last_pair
-      end
-
-      if question.enum_type&.include?("answer_set_closed") ||
-        question.enum_type&.include?("answer_set_open")
-        votation_answer_sets(question)
-      end
+    poll_answers = ::Poll::Answer.by_question(@poll.question_ids).by_author(current_user&.id)
+    poll_answers.each do |answer|
+      @answers_by_question_id[answer.question_id] = answer.answer
     end
 
     @commentable = @poll
@@ -55,18 +42,6 @@ class PollsController < ApplicationController
 
   private
 
-    def votation_answer_sets(question)
-      if question.votation_type.votation_set_answers.by_author(current_user).empty?
-        question.question_answers&.sample(question.max_groups_answers).each do |question_answer|
-          answer = VotationSetAnswer.new(answer: question_answer.title,
-                                           votation_type: question.votation_type,
-                                           author: current_user)
-          question.votation_type.votation_set_answers << answer
-        end
-        !question.save
-      end
-    end
-
     def load_poll
       @poll = Poll.where(slug: params[:id]).first || Poll.where(id: params[:id]).first
     end
@@ -74,8 +49,4 @@ class PollsController < ApplicationController
     def load_active_poll
       @active_poll = ActivePoll.first
     end
-
-    def generate_and_store_new_pair(question)
-      Poll::PairAnswer.generate_pair(question, current_user)
-    end
 end