fix(package): update cors to version 2.8.3

https://greenkeeper.io/

package.json

@@ -98,7 +98,7 @@
     "cafy": "2.3.0",
     "chalk": "1.1.3",
     "compression": "1.6.2",
-    "cors": "2.8.2",
+    "cors": "2.8.3",
     "cropperjs": "1.0.0-rc",
     "crypto": "0.0.3",
     "debug": "2.6.3",