-Favorites:
-- Add 'likes' to activity, collection of ids of people who liked it.
-- show if you favorited something or not.
-- Don't allow double favorites
-- Address favorites to the followers of the liked activity's author.
+- Add a proper undo activity, find out how to ignore those in twitter api.
+
+WEBSUB:
+
+- Add unsubscription
+- Add periodical renewal