Add Lumen extension

Author: JeffreyWay

src/Extensions/Lumen.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Laracasts\Integrated\Extensions;
+
+use Laracasts\Integrated\Extensions\Traits\LaravelTestCase;
+use Laravel\Lumen\Testing\TestCase;
+use Laracasts\Integrated\Emulator;
+
+abstract class Lumen extends TestCase implements Emulator
+{
+    use LaravelTestCase;
+}