We have two things we call "trigger" right now:

• fedmsg message handled by CoCo which leads to rebuild of something by coco.
• class triggering the rebuild of artifact by calling external build service.

This is confusing. We should change the names to something like this:

• events - The list of classes representing fedmsg messages which are handled by triggers. Currently called "triggers".
• triggers - The list of python classes responsible for triggering rebuild of something. Currently named as "handlers"