docs(getting-started): Remove horizontal scrolling (vuejs#1726)

The JavaScript text in the getting-started example was
too wide and caused overflow / horizontal scrolling in the 
'pre' element.

Author: philwsac

docs/en/essentials/getting-started.md

@@ -30,7 +30,8 @@ Creating a Single-page Application with Vue + Vue Router is dead simple. With Vu
 ### JavaScript
 
 ``` js
-// 0. If using a module system (e.g. via vue-cli), import Vue and VueRouter and then call `Vue.use(VueRouter)`.
+// 0. If using a module system (e.g. via vue-cli), import Vue and VueRouter
+// and then call `Vue.use(VueRouter)`.
 
 // 1. Define route components.
 // These can be imported from other files