fix(package): update react-router-dom to version 5.1.1

Closes #29

Author: greenkeeper[bot]

package.json

@@ -85,6 +85,6 @@
     "fs-extra": "^7.0.1",
     "react": "^16.4.1",
     "react-dom": "^16.4.1",
-    "react-router-dom": "^4.3.1"
+    "react-router-dom": "^5.1.1"
   }
 }