Rename/move column names

In order to have use the use the same colum names for unchanged EU codelists as well as for tailored codelists of this project, we will

• rename the original "code" column to "code-eu"
• rename the original "deu_label" column to "deu_label-eu"

Then we will add the tailored columns with the same name

• code will have all german codes
• deu_label will have all german names for the codes