docs: function isCollationValid(collation) {
    let isValid = true;
    _.forIn(collation, function(value, key) {
      const itemIndex = _.findIndex(COLLATION_OPTIONS, key);
      if (itemIndex === -1) {
        debug('Collation "%s" is invalid bc of its keys', collation);
        isValid = false;
      }
      if (COLLATION_OPTIONS[itemIndex][key].includes(value) === false) {
        debug('Collation "%s" is invalid bc of its values', collation);
        isValid = false;
      }
    });
    return isValid ? collation : false;
  }