Make two utility functions of Tweet classmethods
Add an option to resolve shortened URLs
Update self.screen_name if it is overridden

If no screen_name is passed to get_tweets(), self.screen_name is already
correct. In the other case, the instance variable must be updated to
reflect the new screen name.

This also means that screen_name should be read only after get_tweets().
Add an optional screen_name argument to complete.py

This allows to make a backup of someone who follows you.
Use the entities info from Twitter to munge the URLs
Munge images too