minor word change

Author: danneu

app/assets/javascripts/admin/templates/flags.js.handlebars

@@ -13,7 +13,7 @@
     <tr>
       <th class='user'></th>
       <th class='excerpt'></th>
-      <th class='flaggers'>Flag by</th>
+      <th class='flaggers'>Flagged by</th>
       <th class='last-flagged'></th>
       <th class='action'></th>
     </tr>