public ParsedSorting sortInfo() {
        if (sortSettings == null) sortSettings = new ParsedSorting(name(), "attribute.sorting");
        return this.sortSettings;
    }
This class holds the extracted information after parsing a
"attribute" block, using simple data structures as far as
possible.  Do not put advanced logic here!
@author arnej27959
config-model/src/main/java/com/yahoo/schema/parser/ParsedAttribute.java