Fixed #12812 -- added warning about cyclic imports in contrib.comments. Thanks to Beetle_B, bjourne and philgyford for the reports, and Russ for the wording.
Fixed #12812 -- added warning about cyclic imports in contrib.comments. Thanks to Beetle_B, bjourne and philgyford for the reports, and Russ for the wording.

git-svn-id: 4f9f921b081c523744c7bf24d959a0db39629563@14810 bcc190cf-cafb-0310-a4f2-bffc1f526a37

skevy/django,django-nonrel/django-nonrel,skevy/django,disqus/django-old,django-nonrel/django-nonrel,Instagram/django,jamespacileo/django-france,skevy/django,disqus/django-old,django-nonrel/django-nonrel,jamespacileo/django-france,disqus/django-old,jamespacileo/django-france,Instagram/django,mitsuhiko/django,mitsuhiko/django,mitsuhiko/django,Instagram/django