N°3169 - Add feature to connect Gsuite mail box with OAuth

N°2504 - Add feature to connect Office mail box with OAuth2 for Microsoft Graph
N°5102 - Allow to send emails (eg. notifications) using GSuite SMTP and OAuth

sources/Core/Authentication/Client/OAuth/IOAuthClientProvider.php

@@ -0,0 +1,5 @@
+<?php
+namespace Combodo\iTop\Core\Authentication\Client\OAuth;
+
+interface IOAuthClientProvider{
+}