Laravel 5.6 updates

Travis config update

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

vendor/symfony/finder/Tests/Iterator/FilterIteratorTest.php

@@ -1,53 +0,0 @@
-<?php
-
-/*
- * This file is part of the Symfony package.
- *
- * (c) Fabien Potencier <fabien@symfony.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-namespace Symfony\Component\Finder\Tests\Iterator;
-
-/**
- * @author Alex Bogomazov
- *
- * @group legacy
- */
-class FilterIteratorTest extends RealIteratorTestCase
-{
-    public function testFilterFilesystemIterators()
-    {
-        $i = new \FilesystemIterator($this->toAbsolute());
-
-        // it is expected that there are test.py test.php in the tmpDir
-        $i = $this->getMockForAbstractClass('Symfony\Component\Finder\Iterator\FilterIterator', array($i));
-        $i->expects($this->any())
-            ->method('accept')
-            ->will($this->returnCallback(function () use ($i) {
-                return (bool) preg_match('/\.php/', (string) $i->current());
-            })
-        );
-
-        $c = 0;
-        foreach ($i as $item) {
-            ++$c;
-        }
-
-        $this->assertEquals(1, $c);
-
-        $i->rewind();
-
-        $c = 0;
-        foreach ($i as $item) {
-            ++$c;
-        }
-
-        // This would fail in php older than 5.5.23/5.6.7 with \FilterIterator
-        // but works with Symfony\Component\Finder\Iterator\FilterIterator
-        // see https://bugs.php.net/68557
-        $this->assertEquals(1, $c);
-    }
-}