Remove the vendor directory in .gitignore as these dependencies are needed for php-imap

plugins/php-imap/vendor/phar-io/manifest/src/values/Email.php

@@ -0,0 +1,35 @@
+<?php declare(strict_types = 1);
+/*
+ * This file is part of PharIo\Manifest.
+ *
+ * Copyright (c) Arne Blankerts <arne@blankerts.de>, Sebastian Heuer <sebastian@phpeople.de>, Sebastian Bergmann <sebastian@phpunit.de> and contributors
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ */
+namespace PharIo\Manifest;
+
+use const FILTER_VALIDATE_EMAIL;
+use function filter_var;
+
+class Email {
+    /** @var string */
+    private $email;
+
+    public function __construct(string $email) {
+        $this->ensureEmailIsValid($email);
+
+        $this->email = $email;
+    }
+
+    public function asString(): string {
+        return $this->email;
+    }
+
+    private function ensureEmailIsValid(string $url): void {
+        if (filter_var($url, FILTER_VALIDATE_EMAIL) === false) {
+            throw new InvalidEmailException;
+        }
+    }
+}