Audit mode proposal

The combination of these last 2 lines seem like they duplicate each other - it might just be because they both say 'test'.  How do you feel about something like:

```
As a maintainer of a Chef-managed infrastructure,
I want the ability to write infrastructure audits
so that I can validate state in a soon-to-be-managed infrastructure
and validate resources after they are idempotently converged
```

Nevermind, don't use what I wrote, that looks like word vomit :smile: But I think we can make this motivation both more concise and better illustrate _why_ we want audits.