add support for new error type openApiErr.

lib/error.js

@@ -0,0 +1,12 @@
+/**
+ * constructor openApiErr
+ * @constructor
+ * @param {*} message errorMessage
+ */
+function openApiErr(message) {
+  this.message = message || '';
+}
+
+openApiErr.prototype = Error();
+
+module.exports = openApiErr;