Add CounterRepositoryInterface

contracts/CounterRepositoryInterface.php

@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of GitHub Profile Views Counter.
+ *
+ * (c) Anton Komarev <anton@komarev.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Contracts\Komarev\GitHubProfileViewsCounter;
+
+interface CounterRepositoryInterface
+{
+    public function getCount(): int;
+
+    public function incrementCount(): void;
+}