Remove reference to other array handles.

If you want to use other array handles, you have to include them.
Make header testing even smarter about when to enable thrust tests.

Previously we always presumed the OMP system to be around, now we
are smarter and look at thrust version to. If we are above 1.6 we
can use the cpp system.
Add support for OpenGL interop to Dax.

We are adding a new opengl namespace with functions that will
take an array handle and transfer its contents to a given opengl
buffer.