remove rever dependency for dialog

notebook/static/base/js/dialog.js

@@ -5,7 +5,6 @@ define(function(require) {
     "use strict";
 
     var CodeMirror = require('codemirror/lib/codemirror');
-    var IPython = require('base/js/namespace');
     var $ = require('jquery');
     
     /**
@@ -205,8 +204,5 @@ define(function(require) {
         edit_metadata : edit_metadata,
     };
 
-    // Backwards compatability.
-    IPython.dialog = dialog;
-
     return dialog;
 });

notebook/static/base/js/namespace.js

@@ -6,6 +6,7 @@ define(function(){
     var utils = require('base/js/utils');
     IPython.security = require('base/js/security');
     IPython.keyboard = require('base/js/keyboard');
+    IPython.dialog = require('base/js/dialog');
     IPython.utils = utils;
     IPython.load_extensions = utils.load_extensions;