chore(package): update react-router-config to version 5.1.1

Closes #32

Author: greenkeeper[bot]

package.json

@@ -79,7 +79,7 @@
     "onchange": "^3.0.2",
     "react": "^15.6.1",
     "react-router": "^4.2.0",
-    "react-router-config": "^1.0.0-beta.4",
+    "react-router-config": "^5.1.1",
     "rimraf": "^2.5.4",
     "snazzy": "^6.0.0",
     "source-map-support": "^0.5.0",