- Cloneable is a trait with a single protected member 'clone', which is mapped
to java.lang.Cloneable on JVM
- 'clone' is non-abstract to be able to call 'super.clone()' in the
implementations. Also if you need your class to be Cloneable, most of the
time inheriting from Cloneable and calling 'super.clone()' will work
- hack 'super.clone()' in JVM intrinsics and TImpl delegation generation
- make arrays Cloneable, handle 'clone()' calls in the intrinsic
#KT-4890 Fixed
