Add jump point for sr-only jump link.

themes/bootstrap3/templates/layout/layout.phtml

@@ -157,7 +157,7 @@ JS;
       </div>
     </header>
     <div role="main" class="main template-dir-<?=$this->templateDir?> template-name-<?=$this->templateName?>">
-      <div class="container">
+      <div id="content" class="container">
         <?=$this->layout()->content ?>
       </div>
     </div>