Add validateAccessToken endpoint

src/Api/Root.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace TwitchApi\Api;
+
+trait Root
+{
+    /**
+     * Check if an access token is valid
+     *
+     * @param string accessToken
+     * @return array|json
+     */
+    public function validateAccessToken($accessToken)
+    {
+        return $this->get('', [], $accessToken);
+    }
+}

src/TwitchApi.php

@@ -12,6 +12,7 @@
 use TwitchApi\Api\Communities;
 use TwitchApi\Api\Games;
 use TwitchApi\Api\Ingests;
+use TwitchApi\Api\Root;
 use TwitchApi\Api\Search;
 use TwitchApi\Api\Streams;
 use TwitchApi\Api\Teams;
@@ -33,6 +34,7 @@ class TwitchApi extends TwitchRequest
     use Communities;
     use Games;
     use Ingests;
+    use Root;
     use Search;
     use Streams;
     use Teams;