Add vue-router to example

Author: ktquez

demo/package.json

@@ -10,7 +10,8 @@
     "build": "cross-env NODE_ENV=production webpack --progress --hide-modules"
   },
   "dependencies": {
-    "vue": "^2.5.11"
+    "vue": "^2.5.11",
+    "vue-router": "^3.0.1"
   },
   "browserslist": [
     "> 1%",

package.json

@@ -5,7 +5,7 @@
   "main": "dist/vue-axe.js",
   "scripts": {
     "dev": "rollup --config rollup.config.dev.js --watch",
-    "dist": "rollup --config rollup.config.prod.js",
+    "dist": "rollup --config rollup.config.prod.js --environment NODE_ENV:production",
     "release": "standard-version",
     "test": "node_modules/.bin/cypress run",
     "test:open": "node_modules/.bin/cypress open",