Ensures that user-provided PersonName is converted to PersonName instance in python3
Ensures that user-provided PersonName is converted to PersonName instance in python3

If the user manually specifies a person name, then we want to ensure that it is properly converted to a PersonName instance (in python3 only since we didn't do this previously). This ensures that we can properly encode the PersonName during file writing.

carlomt/dicom_tools,carlomt/dicom_tools