Fixed #17675 -- Changed the implementation of the {% regroup %} template tag...

Fixed #17675 -- Changed the implementation of the {% regroup %} template tag to use the context properly when resolving expressions.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@17522 bcc190cf-cafb-0310-a4f2-bffc1f526a37