Laravel 5.6 updates

Travis config update

Removed HHVM script as Laravel no longer support HHVM after releasing 5.3

vendor/symfony/routing/Tests/Loader/FileLocatorStub.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Symfony\Component\Routing\Tests\Loader;
+
+use Symfony\Component\Config\FileLocatorInterface;
+
+class FileLocatorStub implements FileLocatorInterface
+{
+    public function locate($name, $currentPath = null, $first = true)
+    {
+        if (0 === strpos($name, 'http')) {
+            return $name;
+        }
+
+        return rtrim($currentPath, '/').'/'.$name;
+    }
+}