chore(package): update typescript to version 2.3.1

https://greenkeeper.io/

Author: greenkeeper[bot]

package.json

@@ -47,7 +47,7 @@
     "tslint": "5.1.0",
     "tslint-loader": "3.5.3",
     "typedoc": "0.6.0",
-    "typescript": "2.2.2",
+    "typescript": "2.3.1",
     "webpack": "2.4.0"
   },
   "scripts": {