Resolved Admin Issue with Creating Person

Resolved the issue where a person could not be created through the admin
interface due to unpermitted parameters via active admin.
Resolved Admin View/Edit Issue with People

Resolved an issue in active admin with viewing and editing a person.
The default finder searches for an ID but in this instance, a slug is
being used. Because of this we need to find the person based on the
slug.
Merge pull request #1 from jaymiejones86/master

Active Admin Person CRUD Fixes