docs: add installation instructions using Vue CLI (#3206)

[skip ci]
* docs: add installation instructions using Vue CLI

* Update docs/installation.md

Co-authored-by: Eduardo San Martin Morote <[email protected]>

Author: gtsiolis

docs/installation.md

@@ -32,6 +32,14 @@ Vue.use(VueRouter)
 
 You don't need to do this when using global script tags.
 
+## Vue CLI
+
+If you have a project using [Vue CLI](https://cli.vuejs.org/) you can add Vue Router as a plugin. You can let the CLI generate the code above for you as well as two sample routes. **It will also overwrite your `App.vue`** so make sure to backup up the file before running the following command inside your project:
+
+```sh
+vue add router
+```
+
 ## Dev Build
 
 You will have to clone directly from GitHub and build `vue-router` yourself if