def from_user(s)
      case s
      when Twitter::Tweet
        s.user.screen_name
      when Twitter::User
        s.name
      when String
        s
      end
    end
def from_user(s)
      case s
      when Twitter::Tweet
        s.user.screen_name
      when Twitter::User
        s.name
      when String
        s
      end
    end
Pull the username from a tweet hash -- this is different depending on
 if we're doing a search, or parsing through replies/mentions.