ENH: Update SpatialObjects for MetaIO v1

[aylward]

When reading/writing spatial objects via Meta, provide the option of using MetaIO version 1, which fixes bugs in the original MetaIO and SpatialObject implementations.

Specifically,

• ElementOrigin, ElementDirection, and ElementSpacing are used for the image index to physical space transform specification
• TransformMatrix, Position, and CenterOfRotation are used for the object-to-parent transform in the spatialobject scene graph.

Note that this PR is dependent on PR https://github.com/InsightSoftwareConsortium/ITK/pull/4739 being merged.

[aylward]

This PR is dependent on PR https://github.com/InsightSoftwareConsortium/ITK/pull/4739 being merged.

[dzenanz]

With PR #4739 being merged, please rebase this PR.