public void addEnumDef(String id, List<String> vals, String defVal) {
        List<String> in = new ArrayList<>();
        for (String ins: vals) {
            in.add(ins.trim());
        }
        enumDefs.put(id, new EnumDef(in, defVal));
    }
A value which may be either an url or a path.
config/src/main/java/com/yahoo/vespa/config/ConfigDefinition.java