Removed default config path
Update logging calls
Changed state timestamps to two fields

last_update & last_state_change are two separate things we need to
track.
New function for getting a class from a string
New way of represening an SNS Topic
Major refactor of how reactors are handled

Now reactors dynamically load handlers from config files, and everything
is a bit more pythonic.  Hopefully this will allow for easier creation
of handlers and adding new types of reactors.