ENH: Added tests that were removed during modularization

As part of this topic, refactored TestDataObjectIO to remove
dependencies outside of IO/Geometry.

Change-Id: Icb94df4c3d4c330c36fcfb7c3f8cf6a479ec3a59
Merge topic 'IOGeometry' into master

b4e01469 ENH: Added tests that were removed during modularization