Infragistics Ignite UI upload control and MVC – Where is the HttpContext.User and how to get and set it?

To give you the context – we have SPA ERP to build and we have a very good set of jQuery/HTML5 controls for the UI – Infragistics Ignite UI. After installing the IG Ignite UI I started to experiment with the upload control and read its documentation here, here and here (A better organized documentation seated in one place is needed 🙂 ) and experimenting with the examples we got stuck because :