checkio_dev-28
FIX: Recursive import
ADD: Initial migration, migration for the added_at field
ADD: Urls
checkio_dev_28: change_vote signal has been implemented
checkio_dev_28: renaming
is_upvote() and is_downvote() have been added into model
is_upvote() and is_downvote() have been removed from model
Updated version (checking by positive/negative) of is_upvote() and is_downvote() have been added into model
Model introspection for custom fields has been added.