=== EDIT ========
This issue is now solved in Xcode 8.1. I have checked.
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I don\'t know auto-layout
I'm not sure about storyboards but I've found a temporary solution for xib files. In Utilities panel (right hand panel) select File Inspector tab. Under Interface Builder Document section, select the file to open in "XCode 7.x". It will ask you to confirm that you do not want to use XCode 8 features, save the file and close it.