First draft of "how to use vue.js in gitlab" documentation

Puts back trailing whitespace

Changes after review

Changes after review

Adds Changelog entry

Follow documentation styleguide

changelogs/unreleased/document-how-to-vue.yml

+---
+title: Adds documentation for how to use Vue.js
+merge_request: 8866
+author:

doc/development/frontend.md

@@ -23,6 +23,69 @@ some ideas with React.js as well as Angular.
 
 To get started with Vue, read through [their documentation][vue-docs].
 
+#### How to build a new feature with Vue.js
+**Components, Stores and Services**
+
+In some features implemented with Vue.js, like the [issue board][issue-boards]
+or [environments table][environments-table]
+you can find a clear separation of concerns:
+
+```
+new_feature
+├── components
+│   └── component.js.es6
+│   └── ...
+├── store
+│  └── new_feature_store.js.es6
+├── service
+│  └── new_feature_service.js.es6
+├── new_feature_bundle.js.es6
+```
+_For consistency purposes, we recommend you to follow the same structure._
+
+Let's look into each of them:
+
+**A `*_bundle.js` file**
+
+This is the index file of your new feature. This is where the root Vue instance
+of the new feature should be.
+
+Don't forget to follow [these steps.][page-specific-javascript]
+
+**A folder for Components**
+
+This folder holds all components that are specific of this new feature.
+If you need to use or create a component that will probably be used somewhere
+else, please refer to `vue_shared/components`.
+
+A good thumb rule to know when you should create a component is to think if
+it will be reusable elsewhere.
+
+For example, tables are used in a quite amount of places across GitLab, a table
+would be a good fit for a component.
+On the other hand, a table cell used only in on table, would not be a good use
+of this pattern.
+
+You can read more about components in Vue.js site, [Component System][component-system]
+
+**A folder for the Store**
+
+The Store is a simple object that allows us to manage the state in a single
+source of truth.
+
+The concept we are trying to follow is better explained by Vue documentation
+itself, please read this guide: [State Management][state-management]
+
+**A folder for the Service**
+
+The Service is used only to communicate with the server.
+It does not store or manipulate any data.
+We use [vue-resource][vue-resource-repo] to
+communicate with the server.
+
+The [issue boards service][issue-boards-service]
+is a good example of this pattern.
+
 ## Performance
 
 ### Resources
@@ -294,6 +357,13 @@ For our currently-supported browsers, see our [requirements][requirements].
 [xss]: https://en.wikipedia.org/wiki/Cross-site_scripting
 [scss-style-guide]: scss_styleguide.md
 [requirements]: ../install/requirements.md#supported-web-browsers
+[issue-boards]: https://gitlab.com/gitlab-org/gitlab-ce/tree/master/app/assets/javascripts/boards
+[environments-table]: https://gitlab.com/gitlab-org/gitlab-ce/tree/master/app/assets/javascripts/environments
+[page_specific_javascript]: https://docs.gitlab.com/ce/development/frontend.html#page-specific-javascript
+[component-system]: https://vuejs.org/v2/guide/#Composing-with-Components
+[state-management]: https://vuejs.org/v2/guide/state-management.html#Simple-State-Management-from-Scratch
+[vue-resource-repo]: https://github.com/pagekit/vue-resource
+[issue-boards-service]: https://gitlab.com/gitlab-org/gitlab-ce/blob/master/app/assets/javascripts/boards/services/board_service.js.es6
 
 ## Gotchas