ENH: Update version of DCMTK to 3.6.1_20170529
ENH: Update version of DCMTK to 3.6.1_20170529

DCMTK diff can be seen in https://github.com/InsightSoftwareConsortium/DCMTK/compare/efe1a177eac040b6d41aae0db7714cd970e12bc5...4a843721146eccba2524b011e36bae64a8ae52a0

Change-Id: I014dc99c5bcbcee72275a0026ea9a69ba2a87105

stnava/ITK,stnava/ITK,stnava/ITK,BRAINSia/ITK,malaterre/ITK,vfonov/ITK,LucasGandel/ITK,stnava/ITK,blowekamp/ITK,thewtex/ITK,hjmjohnson/ITK,Kitware/ITK,richardbeare/ITK,InsightSoftwareConsortium/ITK,LucasGandel/ITK,blowekamp/ITK,hjmjohnson/ITK,blowekamp/ITK,LucasGandel/ITK,spinicist/ITK,LucasGandel/ITK,Kitware/ITK,vfonov/ITK,thewtex/ITK,Kitware/ITK,spinicist/ITK,BRAINSia/ITK,vfonov/ITK,InsightSoftwareConsortium/ITK,vfonov/ITK,malaterre/ITK,stnava/ITK,spinicist/ITK,InsightSoftwareConsortium/ITK,malaterre/ITK,blowekamp/ITK,hjmjohnson/ITK,fbudin69500/ITK,vfonov/ITK,richardbeare/ITK,fbudin69500/ITK,thewtex/ITK,blowekamp/ITK,BRAINSia/ITK,fbudin69500/ITK,thewtex/ITK,spinicist/ITK,InsightSoftwareConsortium/ITK,fbudin69500/ITK,thewtex/ITK,BRAINSia/ITK,malaterre/ITK,vfonov/ITK,LucasGandel/ITK,malaterre/ITK,LucasGandel/ITK,InsightSoftwareConsortium/ITK,malaterre/ITK,BRAINSia/ITK,BRAINSia/ITK,fbudin69500/ITK,hjmjohnson/ITK,spinicist/ITK,spinicist/ITK,hjmjohnson/ITK,Kitware/ITK,fbudin69500/ITK,stnava/ITK,hjmjohnson/ITK,vfonov/ITK,stnava/ITK,blowekamp/ITK,Kitware/ITK,richardbeare/ITK,Kitware/ITK,LucasGandel/ITK,blowekamp/ITK,blowekamp/ITK,Kitware/ITK,richardbeare/ITK,richardbeare/ITK,thewtex/ITK,hjmjohnson/ITK,InsightSoftwareConsortium/ITK,malaterre/ITK,fbudin69500/ITK,richardbeare/ITK,vfonov/ITK,spinicist/ITK,InsightSoftwareConsortium/ITK,LucasGandel/ITK,fbudin69500/ITK,BRAINSia/ITK,spinicist/ITK,malaterre/ITK,vfonov/ITK,thewtex/ITK,stnava/ITK,spinicist/ITK,malaterre/ITK,richardbeare/ITK,stnava/ITK