Created navController, BNRDetailViewController

Created a navigation controller. Also created a detail view to show more info about the BNRItem on a different view. Next steps will be to push the detail view controller onto the nav controller to support switching views.
Additional commits for detail view controller.

Didn't do a full commit. All changes for the detail view controller (and its XIB file) are now committed to the repo.
Completed navigation logic.

Clicking on a cell in the items view now takes to you to the detail view for the clicked BNRItem.
items view controller can now pass a BNRItem to the detail view for editing.

Updated the items view controller to assign the selected item to the detail view controller's BNRItem. Also updated viewDidLoad for the detail view controller to assign the BNRItem's properties to the text labels in the view.
Editing of BNRItems in detail view is now supported.

Changes made to a BNRItem in the detail view are saved to the shared store, and the items view now reloads the table when the view appears to pull in the new values.
Add UIBarButton to add items to table.

We're now moving to using a UIBarButton in the nag bar to add BNRItems to the table instead of a dedicated button in the view.
Replaced headerView with editButtonItem in the UI nav header.

The navigation header now has an editButton. Deleted the headerView since it's functionality has been completely moved to the nav header.