Split setup routes and retur inline groups

app/routes/setup.php

@@ -0,0 +1,6 @@
+<?php
+
+// Setup route.
+Route::group(['before' => 'is_setup', 'namespace' => 'CachetHQ\Cachet\Http\Controllers'], function () {
+    Route::controller('/setup', 'SetupController');
+});