chore(package): update @types/node to version 14.0.0

Closes #5

Author: greenkeeper[bot]

package.json

@@ -25,7 +25,7 @@
     "typescript": "^2.6.2"
   },
   "devDependencies": {
-    "@types/node": "^9.3.0",
+    "@types/node": "^14.0.0",
     "nodemon": "^1.14.1",
     "tslint": "5.9.1",
     "ts-node": "^6.0.0"