[1.1.X] Fixed #12281: Added some helpful messages when Go is pressed in admin actions and there

is nothing to do because no action was selected or no items are selected. 

r11837 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@11838 bcc190cf-cafb-0310-a4f2-bffc1f526a37