Multiple changes
- Refactoring to clearly separate the bot driver, the messaging system
and the bot. This will make it easier to replace the Facebook
implementation, or use the bot in other places. All the Facebook logic
is now in facebook.py.
- Fixed race condition for the login and message polling. Now the login
will only be attempted on demand.
- Moved the logging logic to logs.py
- Added test to the CongratBoto
- Added __init__.py files, otherwise the directories are not properly
recognized as Python packages.