Partway through refactoring (AGAIN) the KDE code.
Added a 'separate' method to the DataArray class to spew out ndarrays with original shape
current issue: pickle LOSES the additional attribute that stores this, so there is no 'original_shape' attribute to load again.
TODO: investiagte how pickle serializes an np.ndarray and overload, if possible.  If not then may need a hack to the parallel code that transfers original_shape back again.  Yuck.