View controller styling

View controller styling can be usefull for example when you want to set icon images to your custom view controller.

I noticed that it is not working properly - setter methods were not called at all. I first suspected wrong keys in cas_updateStyling and cas_setNeedsUpdateStyling. However additional call to cas_setNeedsUpdateStyling was required in setView method. Now it works in my case but I'm not sure if I haven't missed something.