Add "Remove jQuery" guide

Author: simonihmig

guides/v3.3.0/addons-and-dependencies/removing-jquery.md

@@ -0,0 +1,24 @@
+Ember relied on jQuery in the past, and it still ships with it by default.
+However, in Ember 3.3 it is an optional dependency that you can opt out from.
+
+To do so, install the [`@ember/optional-features`](https://github.com/emberjs/ember-optional-features) addon
+and disable the `jquery-integration` flag:
+
+```shell
+ember install @ember/optional-features
+ember feature:disable jquery-integration
+```
+
+This will remove jQuery from your `vendor.js` bundle and disable any use of jQuery in Ember itself.
+Now your app will be about 30KB lighter!
+
+## Caveats
+
+Without jQuery, any code that still relies on it will break, especially any usage of
+
+* [`this.$()`](https://www.emberjs.com/api/ember/release/classes/Component/methods/$?anchor=%24) in components
+* `jQuery` or `$` directly as a global, through `Ember.$()` or by importing it (`import jQuery from jquery;`) 
+* global acceptance test helpers like `find()` or `click()`
+* `this.$()` in component tests
+
+Note that this also applies to all addons that your app uses, so make sure they support being used without jQuery.

guides/v3.3.0/pages.yml

@@ -230,6 +230,8 @@
   pages:
     - title: "Managing Dependencies"
       url: "managing-dependencies"
+    - title: "Removing jQuery"
+      url: "removing-jquery"
 
 - title: "Configuring Ember.js"
   url: 'configuring-ember'