Mention that Vue CLI should be installed in Prototyping guide (#5079)

* docs: clarified that we need CLI installed

* docs: added vue-cli to bash script

* Update docs/guide/prototyping.md

Co-Authored-By: Pavan Kumar Sunkara <pavan.sss1991@gmail.com>

Co-authored-by: Pavan Kumar Sunkara <pavan.sss1991@gmail.com>

Author: 2 people

docs/guide/prototyping.md

@@ -1,11 +1,11 @@
 # Instant Prototyping
 
-You can rapidly prototype with just a single `*.vue` file with the `vue serve` and `vue build` commands, but they require an additional global addon to be installed first:
+You can rapidly prototype with just a single `*.vue` file with the `vue serve` and `vue build` commands, but they require a global addon to be installed along with the Vue CLI:
 
 ``` bash
-npm install -g @vue/cli-service-global
+npm install -g @vue/cli @vue/cli-service-global
 # or
-yarn global add @vue/cli-service-global
+yarn global add @vue/cli @vue/cli-service-global
 ```
 
 The drawback of `vue serve` is that it relies on globally installed dependencies which may be inconsistent on different machines. Therefore this is only recommended for rapid prototyping.