post votes: add index page.

app/controllers/post_votes_controller.rb

@@ -1,9 +1,14 @@
 class PostVotesController < ApplicationController
-  before_action :voter_only
+  before_action :voter_only, only: [:create, :destroy]
   skip_before_action :api_check
-  respond_to :js, :json, :xml
+  respond_to :js, :json, :xml, :html
   rescue_with PostVote::Error, status: 422
 
+  def index
+    @post_votes = PostVote.includes(:post, :user).paginated_search(params)
+    respond_with(@post_votes)
+  end
+
   def create
     @post = Post.find(params[:post_id])
     @post.vote!(params[:score])