SwissQR: add Sprain\SwissQrBill and dependencies

htdocs/includes/symfony/validator/ConstraintValidatorFactoryInterface.php

@@ -0,0 +1,25 @@
+<?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\Validator;
+
+/**
+ * Specifies an object able to return the correct ConstraintValidatorInterface
+ * instance given a Constraint object.
+ */
+interface ConstraintValidatorFactoryInterface
+{
+    /**
+     * Given a Constraint, this returns the ConstraintValidatorInterface
+     * object that should be used to verify its validity.
+     */
+    public function getInstance(Constraint $constraint): ConstraintValidatorInterface;
+}