Send e-Mail to all commenters if thank you note is given

app/controllers/request_for_comments_controller.rb

@@ -37,6 +37,13 @@ class RequestForCommentsController < ApplicationController
   def set_thank_you_note
     authorize!
     @request_for_comment.thank_you_note = params[:note]
+    commenters = []
+    @request_for_comment.comments.distinct.to_a.each {|comment|
+      commenters.append comment.user
+    }
+    commenters = commenters.uniq {|user| user.id}
+    commenters.each {|commenter| UserMailer.send_thank_you_note(@request_for_comment, commenter).deliver_now}
+
     respond_to do |format|
       if @request_for_comment.save
         format.json { render :show, status: :ok, location: @request_for_comment }