/**
* Returns an array of objects sorted a-z by prop.
*
* @prop array arr An array of objects.
* @prop array props An array of props to sort against.
* @return array A copy of arr sorted by prop.
*/
export function sortObjectsAz(arr: Array<Object>, props: Array<string>): Array<Object> {
  if (arr.length < 1 || props.length < 1) return arr;

  return [].concat(arr).sort((a, b) => {
    var labelA = getSortProp(a, props);
    var labelB = getSortProp(b, props);
    return (labelA < labelB) ? -1 : (labelA > labelB) ? 1 : 0;
  });
}