enhance checked collections to take a Predicate, not just a type

Enhance the checked collections wrapper to take a Predicate that checks the validity of every element as its inserted, based on some logical condition of the predicate, as opposed to passing a Class<?> and having the only check be an instanceof check. The old type-checked collection wrapper could be rewritten as a special case of a general checked collections wrapper.

This has also been referred to as a "validated" or "mediated" collections wrapper.