FIX: 15 characters not enough to parse some DICOM tags


git-svn-id: https://www.nitrc.org/svn/cmtk/trunk@5004 42a5c34f-2066-0410-bec5-ba365beb4995
ADD: error message if parsing tags fails


git-svn-id: https://www.nitrc.org/svn/cmtk/trunk@5005 42a5c34f-2066-0410-bec5-ba365beb4995