isis-core-applib would be the perfect place to consolidate any internal utility classes such as
NullSafe (common null check idioms), StringExtensions, ordering algorithms, etc ...
but we would want to keep these classes contained, meaning they should not be available for public use, just for internal use within Isis' code-base.
Java 9 has the perfect solution for this. But what can we do in the meantime (with Java 8)?