Add php-cs-fixer to build

.php_cs

@@ -0,0 +1,21 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->in('app')
+    ->in('config');
+
+return PhpCsFixer\Config::create()
+    ->setHideProgress(true)
+    ->setUsingCache(false)
+    ->setRiskyAllowed(true)
+    ->setRules(
+        [
+            '@PSR2'        => true,
+            'strict_param' => true,
+            'array_syntax' => ['syntax' => 'short'],
+            'binary_operator_spaces' => [
+                'align_double_arrow' => true,
+            ],
+        ]
+    )
+    ->setFinder($finder);