MemoryMappedFile and JDK 9+

[Skermin8r]

I see based on closed issues that you don't intend (or really need) to add new features but you need to update MemoryMappedFile for JDK 9 and beyond. Your sun.* references need to be updated.

[subes]

I have a fix available here: invesdwin/invesdwin-context-persistence@e841fe9
Though the sun.* references are still available, it is just that the signature of "map0" has changed for Java 14.