chore(package): update react to version 16.4.2

Closes #18

Author: greenkeeper[bot]

package.json

@@ -45,7 +45,7 @@
     "jest": "^20.0.0",
     "nwb": "~0.17.2",
     "prop-types": "^15.5.10",
-    "react": "^15.4.2",
+    "react": "^16.4.2",
     "react-addons-test-utils": "^15.4.2",
     "react-dom": "^15.4.2",
     "regenerator-runtime": "^0.11.0",