Import: add old value to duplicate namelist vars

namelist2config

@@ -173,7 +173,7 @@ while(<>) {
                 $line =~ s/\s+/ /g;
                 warn("Hey: duplicate key, current value '$value'\n");
                 warn("$.:$line\n"); 
-                $key = '#DUPLICATE# '.$key;
+                $key = "#DUPLICATE# $key: $value";
             }
             $namelist_group->{$key} = [];
             $namelist_variable = $namelist_group->{$key};