first crack at hooks and event listeners
make it easier to assign a single listener class to multiple events, add comments and commented out examples related to events to config file
add phpunit tests for event manager. fix bug in event class. replace file_exists in event manager with something that will respect include paths.
Force event listeners to live in the new listeners directory. Update documenation with new event listeners feature
allow someone to adjust the event listener directory. update documentation. make sure unit test conf is properly updated
Merge branch 'master' into event_listeners_pr

Conflicts:
	lib/Propagator.php
Merge pull request #14 from dealnews/event_listeners_pr

Add events/hooks to propagator and allow external scripts to listen for those events

-- nicely done. Thanks for using similar coding conventions as existing code