fix(package): update react to version 16.3.1

Closes #10

Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
     "isomorphic-fetch": "^2.2.1",
     "moment": "^2.18.1",
     "next": "^3.0.3",
-    "react": "^15.6.1",
+    "react": "^16.3.1",
     "react-bootstrap": "^0.31.2",
     "react-codemirror": "^1.0.0",
     "react-datetime": "^2.9.0",