in order to avoid using stale modules when editing, clear out the @module…

in order to avoid using stale modules when editing, clear out the @module variable after a save(). Then on a subsequent edit, it'll get recreated

cms/static/coffee/src/views/module_edit.coffee

@@ -18,6 +18,7 @@ class CMS.Views.ModuleEdit extends Backbone.View
        XModule.loadModule(@$el.find('.xmodule_display'))
 
   loadEdit: ->
+    if not @module
       @module = XModule.loadModule(@$el.find('.xmodule_edit'))
 
   metadata: ->
@@ -56,7 +57,7 @@ class CMS.Views.ModuleEdit extends Backbone.View
     data.metadata = @metadata()
     @model.save(data).done( =>
       alert("Your changes have been saved.")
-
+      @module = null
       @render()
       @$el.removeClass('editing')
     ).fail( ->