Revamp vtkmDataArray to support general array types
VTK-m has added better support for managing arrays of unknown type since
vtkmDataArray
was created. These changes revamp the implementation to
use these new features and make it more efficient to get values directly
from VTK-m arrays. These should make it easier to add vtkmDataArray
s
to VTK datasets that could be passed back to VTK-m.