API errors are being ignored by Vue Storefront

Hi, I noticed that there's no message returned after order confirmation:

I noticed that apiError function in src/lib/util.js file checks in Error object for errorMessage property, but Error has only message property.

/**  Creates a api error status Express Response object.
 *  @param {express.Response} res  Express HTTP Response
 *  @param {number} [code=200]    Status code to send on success
 *  @param {json} [result='OK']    Text message or result information object
 */
export function apiError (res, errorObj, code = 500) {
  return apiStatus(res, errorObj.errorMessage ? errorObj.errorMessage : errorObj, errorObj.code ? errorObj.code : 500)
}

Correct code should be:

/**  Creates a api error status Express Response object.
 *  @param {express.Response} res  Express HTTP Response
 *  @param {number} [code=200]    Status code to send on success
 *  @param {json} [result='OK']    Text message or result information object
 */
export function apiError (res, errorObj, code = 500) {
  return apiStatus(res, errorObj.message ? errorObj.message : errorObj, errorObj.code ? errorObj.code : 500)
}

Then error notification message is correctly shown:

[andrzejewsky]

@cdshotels-liborpansky Helo, thanks for reporting, do you want to create PR to that?

#384 PR created