code: function getErrorMessage(errors) {
      var fullMessage = '';
      errors.forEach(function (err) {
          var message = ajv.errorsText([err]);
          if (message.indexOf('should NOT have additional properties') < 0) {
              fullMessage += message + os.EOL;
          }
          else {
              fullMessage += message + '. Offending property : ' + err.params.additionalProperty + os.EOL;
          }
      });
      return fullMessage;
  }
docs: Gets a human readable error message from the ajv errors object, using the ajv.errorsText and some custom logic
  @param {Object[]} errors the ajv.errors object
  @returns {String} The human readable error message
  @see Ajv.ajv.errorsText
  @private