fix readme

Author: rodber

README.md

@@ -425,14 +425,19 @@ $workflow = workflow(
     storeThumb: async(
         new StoreFile(),
         file: response('thumb'),
-        path: variable('savePath'),
+        dir: variable('saveDir'),
     ),
     storePoster: async(
         new StoreFile(),
         file: response('poster'),
-        path: variable('savePath'),
+        dir: variable('saveDir'),
     )
 );
+$run = run(
+    $workflow,
+    image: __DIR__ . '/src/php.jpeg',
+    saveDir: __DIR__ . '/src/output/',
+);
 ```
 
 The graph for the Workflow above shows that `thumb` and `poster` run async, just like `storeThumb` and `storePoster` but the `store*` jobs run after the first dependency level gets resolved.