Add ctkDcmSCU class copied from dcmtk master

In order to get new functionality (especially C-GET) we
copy in the latest version of DcmSCU into a ctk-specific
class that can later be removed when the functionality
is in dcmtk itself.

Libs/DICOM/Core/CMakeLists.txt

@@ -29,6 +29,11 @@ SET(KIT_SRCS
   ctkDICOMRetrieve.h
   ctkDICOMTester.cpp
   ctkDICOMTester.h
+  # enhanced DcmSCU class - to be removed when
+  # corresponding functionality is in a 
+  # DCMKT release - see notes in header file.
+  ctkDcmSCU.cc
+
 )
 
 # Abstract class should not be wrapped !