fix design index bug when start start from blank DB.

add delay impressionist.
add several i18n vars

app/views/admin/user_actions/index.html.erb

@@ -1,8 +1,8 @@
 <table class="table">
   <tr>
-    <th>時間</th>
-    <th>使用帳號</th>
-    <th>頁面</th>
+    <th><%= I18n.t 'user_action.time' %></th>
+    <th><%= I18n.t 'user_action.name' %></th>
+    <th><%= I18n.t 'user_action.page' %></th>
   </tr>
 
   <%  @user_actions.each do |user_action| %>