* switch to composer for qrcode and otp dependencies

* move most OTP-related stuff into userhelper
* remove old phpqrcode and otphp libraries

vendor/autoload.php

@@ -0,0 +1,7 @@
+<?php
+
+// autoload.php @generated by Composer
+
+require_once __DIR__ . '/composer/autoload_real.php';
+
+return ComposerAutoloaderInit19fc2ff1c0f9a92279c7979386bb2056::getLoader();