Update CDN links to latest, add cdnjs

CDN version is old

Author: nathanhleung

docs/en/installation.md

@@ -5,8 +5,9 @@
 See [dist folder](https://github.com/vuejs/vue-router/tree/dev/dist). Note the dist files are always the latest stable - it's not update-to-date with the `dev` branch source.
 
 ### CDN
+[jsdelivr](https://cdn.jsdelivr.net/vue.router/0.7.7/vue-router.min.js)
 
-[jsdelivr](https://cdn.jsdelivr.net/vue.router/0.5.2/vue-router.min.js)
+[cdnjs](https://cdnjs.cloudflare.com/ajax/libs/vue-router/0.7.7/vue-router.min.js)
 
 ### NPM