add Revert to the menu bar

IPython/frontend/html/notebook/static/js/menubar.js

@@ -87,6 +87,8 b' var IPython = (function (IPython) {'
         this.element.find('#save_checkpoint').click(function () {
             IPython.notebook.save_checkpoint();
         });
+        this.element.find('#restore_checkpoint').click(function () {
+        });
         this.element.find('#download_ipynb').click(function () {
             var notebook_id = IPython.notebook.get_notebook_id();
             var url = that.baseProjectUrl() + 'notebooks/' +
@@ -221,8 +223,34 b' var IPython = (function (IPython) {'
         this.element.find('#keyboard_shortcuts').click(function () {
             IPython.quick_help.show_keyboard_shortcuts();
         });
+        
+        this.update_restore_checkpoint(null);
+        
+        $([IPython.events]).on('checkpoints_listed.Notebook', function (event, data) {
+            that.update_restore_checkpoint(data);
+        });
+        
+        $([IPython.events]).on('checkpoint_created.Notebook', function (event, data) {
+            that.update_restore_checkpoint(data);
+        });
     };
 
+    MenuBar.prototype.update_restore_checkpoint = function(checkpoint) {
+        if (!checkpoint) {
+            this.element.find("#restore_checkpoint")
+                .addClass('ui-state-disabled')
+                .off('click')
+                .find('a').text("Revert");
+            return;
+        };
+        var d = new Date(checkpoint.last_modified);
+        this.element.find("#restore_checkpoint")
+            .removeClass('ui-state-disabled')
+            .off('click')
+            .click(function () {
+                IPython.notebook.restore_checkpoint_dialog();
+            }).find('a').html("Revert to: <br/>" + d.format("mmm dd HH:MM:ss"));
+    }
 
     IPython.MenuBar = MenuBar;
 

IPython/frontend/html/notebook/static/js/notebook.js

@@ -1696,10 +1696,13 b' var IPython = (function (IPython) {'
             });
 
         }
+        
         // Create the kernel after the notebook is completely loaded to prevent
         // code execution upon loading, which is a security risk.
         if (! this.read_only) {
             this.start_kernel();
+            // load our checkpoint list
+            IPython.notebook.list_checkpoints();
         }
         $([IPython.events]).trigger('notebook_loaded.Notebook');
     };

IPython/frontend/html/notebook/templates/notebook.html

@@ -59,6 +59,8 b' class="notebook_app"'
                 <li id="save_notebook"><a href="#">Save</a></li>
                 <li id="save_checkpoint"><a href="#">Save Checkpoint</a></li>
                 <hr/>
+                <li id="restore_checkpoint"><a href="#">Revert to Checkpoint</a></li>
+                <hr/>
                 <li><a href="#">Download as</a>
                     <ul>
                         <li id="download_ipynb"><a href="#">IPython (.ipynb)</a></li>