BREAKING
What: mitk::ThreeDnTDICOMSeriesReader now never condense blocks
to 3D+t if they do not have a valid origin or instance UID.

Why: Valid data that has no image position (like screenshots)
should not be merge into dynamic image (which would anyways fail
due to the failing OrientationSorter.

How to adapt: If you need to condense images without image position
tag then a dedicated reader must be implemented that modifies the
Condense3DBlocks method