RFR 8154556: Use java.nio.ByteOrder instead of boolean value

[Paul Sandoz]

Hi

Please review:

  http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8154556-vh-nio-byteorder/webrev/ 
<http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8154556-vh-nio-byteorder/webrev/>

This is a small tweak to the VarHandle API. The array and ByteBuffer related 
factory methods on MethodhHandles now accept a java.no.ByteOrder rather than a 
boolean value.

Use of java.no.ByteOrder is considered more readable in code that a boolean 
value, for express big, little or native endianness.

Paul.