Merge branch '5.3' into 5.4

* 5.3:
  Import jquery as the $ variable.

Author: javiereguiluz

frontend/encore/simple-example.rst

@@ -182,7 +182,7 @@ Great! Use ``import`` to import ``jquery`` and ``greet.js``:
       // ...
 
     + // loads the jquery package from node_modules
-    + import jquery from 'jquery';
+    + import $ from 'jquery';
 
     + // import the function from greet.js (the .js extension is optional)
     + // ./ (or ../) means to look for a local file