Fix for black screen when only right view is needed and no back view is ...

...present (when using storyboard).

I was using a storyboard with the sw_right segue to define the right view and sw_front for the front. But all I was getting was a black screen. This is because that try catch block is all in one. So when sw_back fails (if its not needed like in my case) the following two views fail to load too. 

I split up the try catches which fixes the problem and allows any combination of views that you want.