code: function addTrustLine(account, trustline, secret, options, callback) {
    var transaction = createTrustLineTransaction(account, trustline);
    var converter = TxToRestConverter.parseTrustResponseFromTx;
    transact(transaction, this, secret, options, converter, callback);
  }
docs: Grant a trustline to a counterparty
  
  @body
  @param {Trustline} request.body.trustline
  @param {String} request.body.secret
  
  @query
  @param {String "true"|"false"} request.query.validated Used to force request
  to wait until rippled has finished validating the submitted transaction