Package: Updates dependency.

package.json

@@ -50,7 +50,7 @@
     "mkdirp": "^0.5.0",
     "mocha": "^2.0.1",
     "nan": "^1.3.0",
-    "object-assign": "^1.0.0",
+    "object-assign": "^2.0.0",
     "replace-ext": "0.0.1",
     "request": "^2.48.0",
     "shelljs": "^0.3.0"