DICOM: Remove unsafe cast warnings in ctkDICOMRetrieve
DICOM: Remove unsafe cast warnings in ctkDICOMRetrieve

commontk/CTK,laurennlam/CTK,naucoin/CTK,msmolens/CTK,espakm/CTK,151706061/CTK,pieper/CTK,jcfr/CTK,finetjul/CTK,Heather/CTK,AndreasFetzer/CTK,rkhlebnikov/CTK,finetjul/CTK,naucoin/CTK,SINTEFMedtek/CTK,CJGoch/CTK,CJGoch/CTK,151706061/CTK,151706061/CTK,commontk/CTK,SINTEFMedtek/CTK,danielknorr/CTK,ddao/CTK,pieper/CTK,AndreasFetzer/CTK,fedorov/CTK,SINTEFMedtek/CTK,msmolens/CTK,mehrtash/CTK,Heather/CTK,fedorov/CTK,msmolens/CTK,mehrtash/CTK,ddao/CTK,commontk/CTK,151706061/CTK,pieper/CTK,CJGoch/CTK,Sardge/CTK,fedorov/CTK,sankhesh/CTK,pieper/CTK,danielknorr/CTK,SINTEFMedtek/CTK,danielknorr/CTK,vovythevov/CTK,AndreasFetzer/CTK,naucoin/CTK,CJGoch/CTK,lassoan/CTK,jcfr/CTK,laurennlam/CTK,jcfr/CTK,lassoan/CTK,vovythevov/CTK,rkhlebnikov/CTK,espakm/CTK,lassoan/CTK,commontk/CTK,sankhesh/CTK,laurennlam/CTK,laurennlam/CTK,ddao/CTK,Sardge/CTK,CJGoch/CTK,AndreasFetzer/CTK,Sardge/CTK,vovythevov/CTK,sankhesh/CTK,fedorov/CTK,vovythevov/CTK,espakm/CTK,msmolens/CTK,finetjul/CTK,151706061/CTK,mehrtash/CTK,jcfr/CTK,sankhesh/CTK,Heather/CTK,espakm/CTK,mehrtash/CTK,Heather/CTK,jcfr/CTK,Sardge/CTK,ddao/CTK,finetjul/CTK,lassoan/CTK,naucoin/CTK,danielknorr/CTK,rkhlebnikov/CTK,SINTEFMedtek/CTK,rkhlebnikov/CTK