Created by: jmmastey
Per discussion on #1111 (closed), removes items from the left navigation if you aren't allowed the index? action on them.
I'm not 100% happy with the test for this, but this didn't fit well with the feature specs that were already in the app and I didn't want to drag a huge change into a small feature. Let me know if they still need work (and a hint of what you'd prefer would be appreciated).
Thanks!