code: func CiDescByFieldIndex(slice interface{}, index []int) {
  	New(slice, FieldByIndexGetter(index), CaseInsensitiveDescending).Sort()
  }
docs: // Sort a slice in case-insensitive descending order by a list of nested field
  // indices, e.g. 1, 2, 3 to sort by the third field from the struct in the
  // second field of the struct in the first field of each struct in the slice.
  // (Valid for string types.)