in left_nav_bar.html , powerpoint to presentation

OfficeJS/component/left_nav_bar.html

@@ -44,8 +44,8 @@
       New Spreadsheet
     </a>
   </li>
-  <li class="powerpoint left-nav-tools">
-    <a href="#/powerpoint"
+  <li class="presentation left-nav-tools">
+    <a href="#/presentation"
        onclick="javascript:
                 OfficeJS.open({app:'present_slides'});
                 return false;">