Builds a row group from input parameters
@param items
@param name
function rowgroup(items, name) {
    return items.map(([htmlterm, ariaterm], i) => {
        htmlcount += htmlterm.split(', ').length
        ariacount += ariaterm.split(', ').length
        return tr([
            !i && th({
                rowSpan : items.length,
                children : name,
            }),
            td(htmlterm),
            td(ariaterm)
        ])
    })
}