[foreign] RFR: add binder support for panama array carriers

[Maurizio Cimadamore]

Hi,
this patch removes binder support for Java array carriers and rewrires 
array support to use the Panama Array class.

To allow interop from Java arrays and back the following API points have 
been added:

Array<Integer> nativeArray = ...
int[] ia = nativeArray.toArray(int[]::new);

And, the reverse operation is handled by Scope, by having a form of 
native array allocation which takes a Java array initializer:

Array<Integer> newNativeArray = scope.allocateArray(NativeTypes.INT32, ia);

This seems to work pretty well in terms of usability. Under the hood, 
the methods BoundedArray::copyFrom/To use MethodHandles to avoid boxing 
of elements.

I've removed a lot of code that had to do, directly or indirectly, with 
Java array accessors generated by the binder.

Webrev:

http://cr.openjdk.java.net/~mcimadamore/panama/array_carrier/

Cheers
Maurizio