allow selecting codemirror keymap in menu

IPython/html/static/edit/js/menubar.js

@@ -54,6 +54,30 @@ define([
         this.element.find('#menu-replace').click(function () {
             editor.codemirror.execCommand("replace");
         });
+        this.element.find('#menu-keymap-default').click(function () {
+            editor.update_codemirror_options({
+                vimMode: false,
+                keyMap: null
+            });
+        });
+        this.element.find('#menu-keymap-sublime').click(function () {
+            editor.update_codemirror_options({
+                vimMode: false,
+                keyMap: 'sublime'
+            });
+        });
+        this.element.find('#menu-keymap-emacs').click(function () {
+            editor.update_codemirror_options({
+                vimMode: false,
+                keyMap: 'emacs'
+            });
+        });
+        this.element.find('#menu-keymap-vim').click(function () {
+            editor.update_codemirror_options({
+                vimMode: true,
+                keyMap: 'vim'
+            });
+        });
         
         // View
         this.element.find('#menu-line-numbers').click(function () {
@@ -67,6 +91,9 @@ define([
             var text = lineNumbers ? "Hide" : "Show";
             text = text + " Line Numbers";
             that.element.find('#menu-line-numbers').find("a").text(text);
+            var keyMap = editor.codemirror.getOption('keyMap') || "default";
+            that.element.find(".selected-keymap").removeClass("selected-keymap");
+            that.element.find("#menu-keymap-" + keyMap).addClass("selected-keymap");
         });
     };
 

IPython/html/templates/edit.html

@@ -46,6 +46,12 @@ data-file-path="{{file_path}}"
               <ul id="edit-menu" class="dropdown-menu">
                 <li id="menu-find"><a href="#">Find</a></li>
                 <li id="menu-replace"><a href="#">Find &amp; Replace</a></li>
+                <li class="divider"></li>
+                <li>Key Map</li>
+                <li id="menu-keymap-default"><a href="#">Default<i class="fa"></i></a></li>
+                <li id="menu-keymap-sublime"><a href="#">Sublime Text<i class="fa"></i></a></li>
+                <li id="menu-keymap-vim"><a href="#">Vim<i class="fa"></i></a></li>
+                <li id="menu-keymap-emacs"><a href="#">emacs<i class="fa"></i></a></li>
               </ul>
             </li>
             <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown">View</a>