Fixed #17255 -- Removed "as" prefix from new timezone template filter names...

Fixed #17255 -- Removed "as" prefix from new timezone template filter names for the sake of clarity. Cheers to Aymeric Augustin for bearing with me.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17107 bcc190cf-cafb-0310-a4f2-bffc1f526a37