Add missing node-notifier npm dependency

Summary:
local-cli now depends on the node-notifier package but it wasn't listed in package.json.
Closes facebook#15905

Reviewed By: TheSavior

Differential Revision: D5814773

Pulled By: hramos

fbshipit-source-id: 3c397b0a21fea5009f35a69515e70a6d78ece375

package.json

@@ -167,6 +167,7 @@
     "minimist": "^1.2.0",
     "mkdirp": "^0.5.1",
     "node-fetch": "^1.3.3",
+    "node-notifier": "^5.1.2",
     "npmlog": "^2.0.4",
     "opn": "^3.0.2",
     "optimist": "^0.6.1",