Require vue-router

package.json

@@ -22,6 +22,7 @@
     "element-ui": "^1.4.4",
     "form-backend-validation": "^2.0.1",
     "vue-data-tables": "^2.0.4",
-    "vue-i18n": "^7.2.0"
+    "vue-i18n": "^7.2.0",
+    "vue-router": "^2.7.0"
   }
 }