docs: function sortPlaceholdersLower (a, b) {
      var aPlaceholder = a.match(placeholderRegExp)
      var bPlaceholder = b.match(placeholderRegExp)
      // if both contain placeholders then sort the same
      if (aPlaceholder && bPlaceholder) {
          return 0
      }
      // if a contains placeholder then move it down
      if (aPlaceholder) {
          return 1
      }
      // if b contains placeholder and not a then move a up
      if (bPlaceholder) {
          return -1
      }
      // neither contain placeholder - do not change order
      return 0
  }