feat(readme): add questionary link

README.md

@@ -1,6 +1,9 @@
 [![Build Status](https://travis-ci.org/akveo/ngx-admin.svg?branch=master)](https://travis-ci.org/akveo/ngx-admin)
 [![Join the chat at https://gitter.im/ng2-admin/Lobby](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/ng2-admin/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![Dependency Status](https://david-dm.org/akveo/ngx-admin/status.svg)](https://david-dm.org/akveo/ng2-admin)
+
+[Who uses ngx-admin?](https://github.com/akveo/ngx-admin/issues/1645)
+
 # Admin template based on Angular 5+, Bootstrap 4 and <a href="https://github.com/akveo/nebular">Nebular</a>
 <a target="_blank" href="http://akveo.com/ngx-admin/#/pages/dashboard?utm_source=github&utm_medium=ngx_admin_readme&utm_campaign=demo"><img src="https://i.imgur.com/XoJtfvK.gif"/></a>