Composer update

* updated Laravel to v5.6.38
* Added laravel tinker in dev dependencies

vendor/psy/psysh/test/CodeCleaner/Fixtures/ClassWithCallStatic.php

@@ -0,0 +1,20 @@
+<?php
+
+/*
+ * This file is part of Psy Shell.
+ *
+ * (c) 2012-2018 Justin Hileman
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Psy\Test\CodeCleaner\Fixtures;
+
+class ClassWithCallStatic
+{
+    public static function __callStatic($name, $arguments)
+    {
+        // wheee!
+    }
+}