Make DAX_ASSERT_EXEC in release mode not emit unused item warnings.

In debug mode the DAX_ASSERT_EXEC will use the items passed into it, so in
release mode we need to do something so that we don't get false positive warnings
Properly mark up CellAverage Add functor to be used with cuda.
call to indexToConnectivityIndex was missing what namespace it is in.
TestingGridGenerator GetCellConnections now pass back cont objects.

Since cuda cont and exec memory aren't shared and the exec methods
are marked with __device__ signature the GetCellConnections method would
never compile. Now we properly compute on the control side the correct cell
connections for testing.

Also since we tried to pass back to the cont side exec objects any use of methods
that only have exec access would cause segfaults.
Add macros to allow us to test worklets with every device adapter.

nvcc has issues with COMPILE_FLAGS and COMPILE_DEFININTIONS properties, so
we have to add more NVCC_CXX_FLAGS to silence the boost warnings.

We also now properly append to COMPILE_FLAGS and COMPILE_DEFININTIONS so
we don't clobber other info people have set.
Update all unit tests so they can be used with Cuda.
Update worklet tests under cuda to not generate warnings.

The cuda compiler is generating warnings that are pure noise
and I am unable to find a way to silence just that warning so I am
going to silence all warnings when building the worklet tests.
Testing Grid Generator now returns only control side objects.

When using the Testing Grid Generator with the cuda device adapter
the exec::CellVertices and exec::CellField objects are not safe to access
in the host calling code. Now we return special host side classes that
pull down this data to the host.
Merge branch 'refactor_worklet_testing'
Reduce the size of test grids to speed up the unit tests.

Dax unit testing is taking up to 30minutes to run which is starting to become
a barrier to getting features in. So lets reduce the grid size to shave a couple
of minutes of the total time.
Merge branch 'refactor_worklet_testing'