Simplify initialization code for tags links

By using an event delegation handler on document body there is no need
to check if element was already initialized (idempotency) anymore.

app/assets/javascripts/tags.js

@@ -4,9 +4,7 @@
     initialize: function() {
       var $tag_input;
       $tag_input = $("input.js-tag-list");
-      $("body .js-add-tag-link").each(function() {
-        if ($(this).data("initialized") !== "yes") {
-          $(this).on("click", function() {
+      $("body").on("click", ".js-add-tag-link", function() {
         var current_tags, name;
         name = "\"" + ($(this).text()) + "\"";
         current_tags = $tag_input.val().split(",").filter(Boolean);
@@ -17,8 +15,6 @@
         }
         $tag_input.val(current_tags.join(","));
         return false;
-          }).data("initialized", "yes");
-        }
       });
     }
   };