chore(package): update typescript to version 2.3.1

Closes #324

https://greenkeeper.io/

Author: greenkeeper[bot]

package.json

@@ -68,7 +68,7 @@
     "to-string-loader": "1.1.5",
     "tslint": "4.5.1",
     "tslint-react": "2.4.0",
-    "typescript": "2.2.1",
+    "typescript": "2.3.1",
     "typescript-formatter": "5.1.1",
     "url-loader": "0.5.8",
     "validate-commit-msg": "2.11.2",