Created JDownloaderClient.

src/errors/JDownloaderError.js

@@ -0,0 +1,9 @@
+class JDownloaderError extends Error {
+  constructor(message) {
+    super(message);
+    
+    this.name = 'JDownloaderError';
+  }
+}
+
+module.exports = JDownloaderError;

src/errors/index.js

@@ -1,7 +1,9 @@
 const FatalError = require('./FatalError');
 const ScraperError = require('./ScraperError');
+const JDownloaderError = require('./JDownloaderError');
 
 module.exports = {
   FatalError,
-  ScraperError
+  ScraperError,
+  JDownloaderError
 };