Add warning about plugin not working with Xcode 8
Add warning about plugin not working with Xcode 8

Johnykutty/SwiftLint,victorpimentel/SwiftLint,jeffreybergier/SwiftLint,lyft/SwiftLint,lyft/SwiftLint,Johnykutty/SwiftLint,Johnykutty/SwiftLint,jeffreybergier/SwiftLint,firebase/SwiftLint,realm/SwiftLint,firebase/SwiftLint,lyft/SwiftLint,Johnykutty/SwiftLint,jeffreybergier/SwiftLint,victorpimentel/SwiftLint,firebase/SwiftLint,jeffreybergier/SwiftLint,realm/SwiftLint,victorpimentel/SwiftLint,firebase/SwiftLint,lyft/SwiftLint,realm/SwiftLint,realm/SwiftLint,victorpimentel/SwiftLint