Adds user defaults controller
Adds userdefaultscontroller, defaults browser, defaults item models.
Updates main developer controller to provide access to the user defaults browser
Adds ability to enable edit mode
Adds function to defaults controller to delete defaults
Implements deletion method of user defaults objects into tableview
Adds forward class declaration to prevent build error
Re-works defaults controller to support refreshing
Enables KVO on defaults controller to refresh viewController whenever an item is deleted
Merge branch 'feature/user_defaults_panel' into develop