Update dependencies.

[ddeklerk]

I am using this package in a Meteor app, and unfortunately it is causing some trouble when deploying on Galaxy. When deployed with this package I get the following error.

Error: Cannot find module 'object-assign'

This causes the app to crash. When I remove the package and re-deploy the app to Galaxy, all is fine.

Besides that, the package still has React 0.14 as a dependency, which is outdated.