Audit Mode Formatter Integration

@mcquin 

Right now I only have the STDOUT formatter tied into the event bus.  I'm going to add the JSON formatter and update this review, but I wanted to get it started.
`super` with no arguments passes arguments. Not sure what happens if you do `super()`. Depending on whether you control the code that calls `#initialize` you may decide it's better to do:

```ruby
def initialize(*args)
  super
  # do your own thing here
end
```

Or you could remove this method since it's not actually doing anything right now.