BUG: improve loading of DICOM referenced datasets
Created by: fedorov
See issue http://www.na-mic.org/Bug/view.php?id=3952
- try to improve the sizing policy for the popup (works as expected on Mac)
- make popup modal
- add checks for the referenced datasets that will prevent them from being loaded when the list of files for the referenced dataset matches the one user already selected in the DICOM widget GUI
@cpinter could you please review if it addresses the issue?