rename similar posts to recommended posts, refactor menu on posts/show

app/logical/post_sets/recommended.rb

@@ -0,0 +1,20 @@
+module PostSets
+  class Recommended < PostSets::Post
+    def initialize(post)
+      super("")
+      @post = post
+    end
+
+    def posts
+      @posts ||= begin
+        response = RecommenderService.similar(@post)
+        post_ids = response.reject {|x| x[0] == @post.id}.slice(0, 6).map {|x| x[0]}
+        ::Post.find(post_ids)
+      end
+    end
+
+    def presenter
+      ::PostSetPresenters::Post.new(self)
+    end
+  end
+end