function objToStrings (obj) {
  const vet = Object.keys(obj).sort()
  const strObj = {}
  for (let i = 0; i < vet.length; i++) { strObj[vet[i]] = stri(obj[vet[i]]) }
  return strObj
}
Transform Obj properties in an array of string-converted values of
its sorted properties

Syntax:

    objToString(obj)

@param  {object} obj     The input object
@return {array}          Arrey of sorted properties converted to strings