Add conditional and exclusionary auditing feature

Closes #2
Upstream #167

Squashed commit of the following:

commit 98cb3bf9cf5b3f2cf030c615f51a294b03043d30
Author: Valentino <valentino@reenhanced.com>
Date:   Thu Feb 6 15:32:11 2014 -0500

    Add updates to docs and add tests for mongo

commit 4ae4c83de8be88afe22b3c5932e6947710546a3f
Author: Valentino <valentino@reenhanced.com>
Date:   Thu Feb 6 15:13:20 2014 -0500

    Add conditional and exclusionary auditing feature