minor #793 Add a Request use statements to the controller (weaverryan)

This PR was merged into the 2.3 branch.

Discussion
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Add a Request use statements to the controller

Hiya guys!

Beginners build off of this controller, including copying it to create second/third controllers. Since needing the `$request` object is so common, and getting it involves type-hinting the Request argument, I think this helps.

Thanks!

Commits
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8b84461 It's common to need the request, which you get from type-hinting. Adding the use helps to remove a step for users in the future

Author: fabpot

src/AppBundle/Controller/DefaultController.php

@@ -4,6 +4,7 @@
 
 use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
 use Symfony\Bundle\FrameworkBundle\Controller\Controller;
+use Symfony\Component\HttpFoundation\Request;
 
 class DefaultController extends Controller
 {